In this paper, the gravitational deflection of relativistic massive particles up to the second post-Minkowskian order by static and spherically symmetric wormholes is investigated in the weak-field limit. These wormholes include the Janis-Newman-Winicour wormhole, a class of zero Ricci scalar scalar-tensor wormholes, and a class of charged Einstein-Maxwell-dilaton wormholes. With the Jacobi metric approach, the Gauss-Bonnet theorem is employed to study the gravitational deflection. In this scheme, the deflection angle as a topological effect is considered. Moreover, we analyze the influence of the spacetime parameters on the results. PACS numbers: 98.62.Sb, 95.30.Sf

We consider the coherence-vector representation of a bipartite state and obtain a necessary and sufficient condition for a zero-discord state. Based on this, a measure of quantum, classical, and total amount of correlations in bipartite states is proposed in this representation. Analytical expressions for this measure are available for any bipartite states. Our measure of nonclassical correlation coincides with the geometric measure of quantum discord for some particular states. I. INTRODUCTIONCharacterizing and quantifying the correlations in bipartite states is a basic and significant problem in quantum physics. The study of quantum correlations has traditionally focused on entanglement [1], which plays an important role in quantum computation and quantum communication [2]. However, quantum entanglement is not the only kind of correlation and is not necessary for deterministic quantum computation with one pure qubit (DQC1) [3,4]. These led to the studies on other kinds of nonclassical correlations over the past decade. One of the measures for nonclassical correlations, the quantum discord, initially introduced by Ollivier and Zurek [5] and by Henderson and Vedral [6], has attracted much attention recently [7][8][9][10][11][12][13][14].Given a bipartite state ρ AB on a composite Hilbert space H AB = H A ⊗ H B , the total amount of correlations is quantified by the quantum mutual information I (ρ AB ) = S(ρ A ) + S(ρ B ) − S(ρ AB ), with S(ρ) = −Trρ log 2 ρ the von Neumann entropy and ρ A(B) = Tr B(A) ρ AB the reduced density matrices for subsystem A(B). The quantum discord is defined as Q(ρ AB ) = I (ρ AB ) − J A (ρ AB ), the discrepancy between the quantum mutual information I (ρ AB ) and its classical version J A (ρ AB ) = S(ρ B ) − min { A

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In our paper, the parameter b in Eqs. (25), (27)-(29) should be replaced by 2b. The conclusions of our paper are not affected. Consequently, the b parameter in Fig. 1 should read 0.25 instead of 0.5.In detail, Eqs. (25), (27)-(29) should read

This paper focuses on speed and current sensor fault detection and isolation (FDI) for induction motor (IM) drives. A new, accurate and high-efficiency FDI approach is proposed so that a system can continue operating with good performance even in the presence of speed sensor faults, current sensor faults or both. The proposed three paralleled adaptive observers are capable of current sensor fault detection and localization. By using observers, the rotor flux and rotor speed can be estimated which allows the system to run under the speed sensorless vector control mode when a speed sensor fault occurs. In order to detect speed sensor faults, a threshold-based scheme is proposed. To verify the feasibility and effectiveness of the proposed FDI strategy, experiments are carried out under different conditions based on a dSPACE DS1104 induction motor drive platform.