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51.
Rabindra N. Mohapatra Goran Senjanović 《Zeitschrift fur Physik C Particles and Fields》1983,20(4):365-367
We suggest soft breaking of Peccei-Quinn symmetry as a simple solution to the strongCP problem without the presence of the axion. In the context of theSU(2) L ×U(1) model, it is shown how settingθ tree=0 keeps θ calculable and, furthermore, extremely small: θ?10?16. Unlike in the case of the axion the model is free from the cosmological domain wall problem. Possible extension of this idea to grand unification is discussed. 相似文献
52.
The fluctuating elastic boundary (FEB) model for molecular dynamics has recently been developed and validated through simulations of liquid argon. In the FEB model, a flexible boundary which consists of particles connected by springs is used to confine the solvated system, thereby eliminating the need for periodic boundary conditions. In this study, we extend this model to the simulation of bulk water and solvated alanine dipeptide. Both the confining potential and boundary particle interaction functions are modified to preserve the structural integrity of the boundary and prevent the leakage of the solute-solvent system through the boundary. A broad spectrum of structural and dynamic properties of liquid water are computed and compared with those obtained from conventional periodic boundary condition simulations. The applicability of the model to biomolecular simulations is investigated through the analysis of conformational population distribution of solvated alanine dipeptide. In most cases we find remarkable agreement between the two simulation approaches. 相似文献
53.
Robert D.?Carr Harvey J.?GreenbergEmail author William E.?Hart Goran?Konjevod Erik? Lauer Henry?Lin Tod?Morrison Cynthia A.?Phillips 《Mathematical Programming》2006,107(1-2):337-356
We present a series of related robust optimization models for placing sensors in municipal water networks to detect contaminants
that are maliciously or accidentally injected. We formulate sensor placement problems as mixed-integer programs, for which
the objective coefficients are not known with certainty. We consider a restricted absolute robustness criteria that is motivated
by natural restrictions on the uncertain data, and we define three robust optimization models that differ in how the coefficients
in the objective vary. Under one set of assumptions there exists a sensor placement that is optimal for all admissible realizations
of the coefficients. Under other assumptions, we can apply sorting to solve each worst-case realization efficiently, or we
can apply duality to integrate the worst-case outcome and have one integer program. The most difficult case is where the objective
parameters are bilinear, and we prove its complexity is NP-hard even under simplifying assumptions. We consider a relaxation
that provides an approximation, giving an overall guarantee of near-optimality when used with branch-and-bound search. We
present preliminary computational experiments that illustrate the computational complexity of solving these robust formulations
on sensor placement applications. 相似文献
54.
In this paper, we construct combinatorial bases of Feigin–Stoyanovsky’s type subspaces of standard modules for level k affine Lie algebra \(C_\ell ^{(1)}\). We prove spanning by using annihilating field \(x_\theta (z)^{k+1}\) of standard modules. In the proof of linear independence, we use simple currents and intertwining operators whose existence is given by fusion rules. 相似文献
55.
Goran Djanković 《Czechoslovak Mathematical Journal》2013,63(3):833-845
Classical Kloosterman sums have a prominent role in the study of automorphic forms on GL2 and further they have numerous applications in analytic number theory. In recent years, various problems in analytic theory of automorphic forms on GL3 have been considered, in which analogous GL3-Kloosterman sums (related to the corresponding Bruhat decomposition) appear. In this note we investigate the first four power-moments of the Kloosterman sums associated with the group SL3(?). We give formulas for the first three moments and a nontrivial bound for the fourth. 相似文献
56.
Vladimir Stojanović Predrag Kozić Goran Janevski 《Journal of sound and vibration》2013,332(3):563-576
A general procedure for the determination of the natural frequencies and buckling load for a set of beam system under compressive axial loading is investigated using Timoshenko and high-order shear deformation theory. It is assumed that the set beams of the system are simply supported and continuously joined by a Winkler elastic layer. The model of beam includes the effects of axial loading, shear deformation and rotary inertia. In the special case of identical beams, explicit expressions for the natural frequencies and the critical buckling load are determined using a trigonometric method. The influences of the compressive axial loading and the number of beams in the system on the natural frequencies and the critical buckling load are discussed. These results are of considerable practical interest and have wide application in engineering practice of frameworks. 相似文献
57.
58.
Miroslav M. Ristić Muna M. Aoneas Mirjana M. Vojnović Sava M. D. Galijaš Goran B. Poparić 《Plasma Chemistry and Plasma Processing》2018,38(4):903-916
Electron impact excitation rate coefficients for singlet and triplet electronic states of the carbon monoxide molecule have been calculated under non-equilibrium conditions in the presence of radio-frequency electric field. A Monte Carlo simulation of electron transport has been performed in order to determine non-equilibrium electron energy distribution functions within one period of applied electric field. By using these distribution functions and corresponding cross sections, the excitation rate coefficients have been calculated for all electronic states of CO in the frequency range from 13.56 up to 500 MHz, at reduced root mean square electric field values ranging from 200 to 700 Td. We expect these rates to be valuable for modeling radio-frequency CO plasmas since excited neutrals exhibit greater chemical reactivity than neutrals in ground electronic state, hence altering many properties of plasma. 相似文献
59.
Aleksandra Minić Jovana P. Bugarinović Anka Pejović Danijela Ilić Komatina Goran A. Bogdanović Ivan Damljanović Dragana Stevanović 《Tetrahedron letters》2018,59(38):3499-3502
A simple one-pot synthesis of new ferrocene-containing 1,3-thiazinan-2-imines from 3-arylamino-1-ferrocenylpropan-1-ols and phenyl isothiocyanate has been developed. The key intermediate β-hydroxy thioureas were generated in situ using ultrasound irradiation and subsequent cyclization was achieved by the addition of acetic acid. The scope of the reaction towards various 3-arylamino-1-ferrocenylpropan-1-ols has been explored and the corresponding 3-aryl-6-ferrocenyl-N-phenyl-1,3-thiazinan-2-imines were obtained in moderate to high yields (52–90%). 相似文献
60.
Inside Back Cover: The Solution of the Puzzle of Smectic‐Q: The Phase Structure and the Origin of Spontaneous Chirality (Angew. Chem. Int. Ed. 11/2018) 下载免费PDF全文