Modular transformation and twist between trigonometric limits of sl(n)sl(n) elliptic R-matrix

We study the modular transformation of ${\bf Z}_n$-symmetric elliptic R-matrix and construct the twist between the trigonometric degeneracy of the elliptic R-matrix.Comment: 8 pages, latex, reference revise

Adiabatic Connection for Strictly-Correlated Electrons

Modern density functional theory (DFT) calculations employ the Kohn-Sham (KS) system of non-interacting electrons as a reference, with all complications buried in the exchange-correlation energy (Exc). The adiabatic connection formula gives an exact expression for Exc. We consider DFT calculations that instead employ a reference of strictly-correlated electrons. We define a "decorrelation energy" that relates this reference to the real system, and derive the corresponding adiabatic connection formula. We illustrate this theory in three situations, namely the uniform electron gas, Hooke's atom, and the stretched hydrogen molecule. The adiabatic connection for strictly-correlated electrons provides an alternative perspective for understanding density functional theory and constructing approximate functionals.Comment: 4 figures, has been published in J. Chem. Phy

Free boson representation of DYℏ(sl^(M+1∣N+1))DY_{\hbar}(\hat{sl} (M+1|N+1)) at level one

We construct a realization of the central extension of super-Yangian double $DY_{\hbar}(\hat{sl}(M+1|N+1))$ at level-one in terms of free boson fields with a continuous parameter.Comment: 9 pages, latex, reference revise

Forecasting of global horizontal irradiance by exponential smoothing, using decompositions

Time series methods are frequently used in solar irradiance forecasting when two dimensional cloud information provided by satellite or sky camera is unavailable. ETS (exponential smoothing) has received extensive attention in the recent years since the invention of its state space formulation. In this work, we combine these models with knowledge based heuristic time series decomposition methods to improve the forecasting accuracy and computational efficiency.<p></p> In particular, three decomposition methods are proposed. The first method implements an additive seasonal-trend decomposition as a preprocessing technique prior to ETS. This can reduce the state space thus improve the computational efficiency. The second method decomposes the GHI (global horizontal irradiance) time series into a direct component and a diffuse component. These two components are used as forecasting model inputs separately; and their corresponding results are recombined via the closure equation to obtain the GHI forecasts. In the third method, the time series of the cloud cover index is considered. ETS is applied to the cloud cover time series to obtain the cloud cover forecast thus the forecast GHI through polynomial regressions. The results show that the third method performs the best among three methods and all proposed methods outperform the persistence models.<p></p&gt

Power of Information Channels: Participation in e-Government Discourse

This study examines the collective use of the electronic information and communication channels and their impact on citizen participation for public discourse. Using both quantitative and qualitative research methods, we investigate public communication channels available for government service provision in a large metropolis in China. Specifically, four electronic communication channels are analyzed to assess the impacts of diverse dimensions for electronic participation from citizens to governmental discourse. Upon completion, the study will provide a useful framework with insights for both researchers and practitioners in the power of electronic information and communication channels in electronic participation in the public discourse

Adiabatic Connection in the Low-Density Limit

In density functional theory (DFT), the exchange-correlation functional can be exactly expressed by the adiabatic connection integral. It has been noticed that as lambda goes to infinity, the lambda^(-1) term in the expansion of W(lambda) vanishes. We provide a simple but rigorous derivation to this exact condition in this work. We propose a simple parametric form for the integrand, satisfying this condition, and show that it is highly accurate for weakly-correlated two-electron systems.Comment: 4 pages, 2 figures, submitted to Phys. Rev.

Charmless hadronic Bc→VA,AAB_c \to VA, AA decays in the perturbative QCD approach

In this work, we calculate the branching ratios (BRs) and the polarization fractions of sixty two charmless two-body $B_c$ meson decays into final states involving one vector and one axial-vector meson ($VA$) or two axial-vector mesons($AA$) within the framework of perturbative QCD (pQCD) approach systematically, where $A$ is either a $^3P_1$ or $^1P_1$ axial-vector meson. All considered decay channels can only occur through the annihilation topologies in the standard model. Based on the perturbative calculations and phenomenological analysis, we find the following results: (i) the CP-averaged BRs of the considered sixty two $B_c$ decays are in the range of $10^{-5}$ to $10^{-9}$; (ii) since the behavior for $^1P_1$ meson is much different from that of $^3P_1$ meson, the BRs of $B_c \to A(^1P_1) (V, A(^1P_1))$ decays are generally larger than that of $B_c \to A(^3P_1) (V, A(^3P_1))$ decays in the pQCD approach; (iii) many considered decays modes, such as $B_c\to a_1(1260)^+ \omega$, $b_1(1235) \rho$, etc, have sizable BRs within the reach of the LHCb experiments; (iv) the longitudinal polarization fractions of most considered decays are large and play the dominant role; (v) the pQCD predictions for several decays involving mixtures of $^3P_1$ and/or $^1P_1$ mesons are highly sensitive to the values of the mixing angles, which will be tested by the ongoing LHC and forthcoming Super-B experiments; (vi) the CP-violating asymmetries of these considered $B_c$ decays are absent in the standard model because only one type tree operator is involved.Comment: 31 pages, 1 figur

Theory of control of optomechanical transducers for quantum networks

We present a scheme of control for the arbitrary optical interface mediated by a nanoscale mechanical oscillator between flying qubits and optical nonactive solid-state qubits. This quantum interface lays the foundation for many key functions of a quantum network, such as transferring, swapping, and entangling qubits between distant nodes of a quantum network. Numerical simulations of the quantum interface operations show high fidelities and robust tolerance under realistic experimental conditions. Compared with a previous scheme, it may significantly increase the speed of state transfer operation of high fidelity