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This letter demonstrates an on-silicon integrated thin film coupled inductor using a novel cascade matrix concept to suit multiphase integrated voltage regulator (IVR) applications. The novel cascade matrix coupled (CMC) stripline inductor facilitates all-phase-coupled configuration to reduce the phase ripple current in IVRs. It also shows excellent scalability and neat floor planning. Moreover, the proposed CMC inductor uses double layer metal scheme for windings and interconnects, which significantly reduces the ac winding resistance. A four-phase CMC inductor has been successfully fabricated on-silicon substrate and characterized, which uses conventional thin film magnetic core deposition process to achieve in-plane magnetic uniaxial anisotropy. The device occupies 3.2 × 1.7 mm2 floor area and provides 19.5 nH phase inductance with 120 mΩ dc resistance. The saturation current for each phase is up to 0.4 A when the phase inductance drops by approximately 20%. The coupling coefficient between any two phases of the proposed CMC inductor is 0.27, much higher and more controllable than that of toroid core-based coupled inductors.

This paper presents the development of an AA battery size electromagnetic vibration energy harvester with an aim to maximize the output power density. A tube shape and stacked opposing permanent magnets with magnetic spring were used to suit the shape constraint as well as to achieve high flux linkages. An initial prototype of electromagnetic vibration harvester with AA battery size was built and tested on a controllable shaker to obtain its output voltage and power level at different frequencies for fixed accelerations. A single magnet was fixed at the bottom of the harvester to provide levitation force in this development in order to lower the resonant frequency. A special time-domain based analytical model was also developed using both Finite Element Analysis and Simulink simulation. The time-domain analytical model is easier to implement than other frequency domain based analytical models which generally applied in literatures for modelling of the electromagnetic vibration energy harvesters. The analytical model was verified by the measured results obtained from the initial prototype. The validated analytical model was successfully applied to optimize the harvester. Two more generator prototypes were further built and tested after the optimization study. The optimized harvester using three stacked opposing permanent magnets could achieve a normalized power density of 12,655 μWcm−3 g−2 at 9.9 Hz frequency with 0.22 g acceleration, which is significantly higher than other reported electromagnetic vibration energy harvesters.

In this article, a large-scale multiplicity flexible job-shop scheduling problem (FJSP) with sequence-dependent set-up time is studied. In this problem, the large production demand for each type of job yields the large-scale multiplicity manufacturing feature. To address the problem, a hybrid fluid master–apprentice evolutionary algorithm (HFMAE) is presented to minimize the makespan. In the first step, a fluid relaxation initialization method (FRI) and an initialize procedure are proposed to obtain high-quality initial solutions. In the FRI, an online fluid tracking policy is presented to improve the assignment decision and the sequencing decision of operations. In the second step, an improved master–apprentice evolutionary method (IMAE) is presented based on the generated initial solutions. In the IMAE, two neighbourhood structures and three makespan estimation approaches are presented to accelerate the solution space search efficiency. Numerical results show that the proposed HFMAE outperforms the comparison algorithms in solving large-scale multiplicity FJSPs.

A micro-inductor has been fabricated on silicon substrate using a Micro-Electromechanical Systems (MEMS) process. The micro-inductor has a single layer copper winding sandwiched between two layers of electroplated NiFe core. It has a footprint area of 2.9 mm2, an inductance of 204 nH at 21.7 MHz, a DC resistance of 470 m Ω , and a peak quality factor of 9.23 at 9.2 MHz. The micro-inductor has been applied in a buck converter and achieved a maximum converter efficiency of 81.74% at 20 MHz. The performance of the micro-inductor has also been compared with an air-core inductor embedded in PCB. The air core inductor has a similar inductance of 220 nH, but with a large footprint area of 32 mm2. The maximum buck converter efficiency is 85.47% when the air core inductor is applied.

An analysis of factors that influence coalbed methane content showed that seven factors had a major influence: coal thickness, methane concentration, vitrinite reflectance, permeability, cracks, and sealing conditions hydrodynamic conditions were selected as criterion indexes. The prediction model of coalbed methane content was built based on the uncertainty measure theory. Data from six regions in the central and southern Qinshui Basin were used as the training sample. The sample mean was set as the cluster centers, and the index weight was determined by information entropy theory. Calculation of the multi-index comprehensive measure of the sample showed that the sample was classified according to the minimum uncertainty measure distance principle, which was used to predict coalbed methane content. The research results show that: the obtained level by the prediction method is consistent with the practical level, the predictive value is basically consistent with the actual value, coalbed methane content prediction method based on uncertainty measure theory is reliable and practical, as well as showing a new way for the prediction and evaluation of coalbed methane content in the future.

This paper presents our continuous effort on multiples attenuation in shallow water environment. The seismic data were acquired at various locations along the offshore of Vietnam, and the interpret...

Variable-depth streamer acquisition, as one of the key marine broadband solutions, has shown great advantages in providing high resolution seismic imaging and better low frequency penetration than conventional data from examples around the world. By utilizing the notch diversity, the receiver ghost was fully removed through proprietary joint deconvolution method in the imaging domain which produces broadband imaging with bandwidth up to six octaves. However, this post-migration deghosting method requires the receiver ghost to be well preserved prior to final migration thus introduces complexity in key steps like multiple attenuation, velocity analysis and migration than the conventional processing flow. The objective of this work is to simplify the processing flow by applying bootstrap deghosting method right after shot domain de-noise. After this step, processing flow will be very similar to the conventional flow. This new flow has been tested on the variable-depth streamer data from NWS Australia. Compared to the post-migration deghosting flow, the new results not only provide similar benefit as to broader bandwidth and rich images, but also show improvement on multiple attenuation and primary preservation as well as seismic inversion.

In this paper, we study the method of moments estimation in a finite mixture where the mixing distribution is supported on [0, 1], and the number of support points is fixed. We prove the validity of the modification method proposed by Lindsay (1989). Further, we demonstrate that the modified estimator is weakly consistent and that its convergence rate is \(N^{ - \tfrac{1} {2}} (\log \log N)^{\tfrac{1} {2}} \).

The ionic liquid 1,1,3,3-tetramethylguanidinium lactate (TMGL) was supported onto porous silica particles via a facile impregnation−vaporization method. The TMGL-supported particles gave high porosity and large specific surface area. The SO2 sorption/desorption properties of the silica-supported TMGL (TMGL−SiO2) were evaluated, and high SO2 sorption capacity and rate were achieved. Its capacity reached 0.6 g SO2/g TMGL in 15−30 min with pure SO2 gas and 0.15 g SO2/g TMGL in 17 h with a N2/SO2 mixture gas that contained 2160 ppm SO2. The SO2 concentration was reduced to 12.6 ppm after sorption. The TMGL−SiO2 system could be reused for many sorption/desorption cycles without change in its capacity. It was also characterized by good mechanical strength and thermal stability at temperature up to 130 °C. The SO2 sorbent system appears to be useful in gas desulfurization.

Quantum discord, as defined by Olliver and Zurek (2002 Phys. Rev. Lett. 88 017901) as the difference of two natural quantum extensions of the classical mutual information, plays an interesting role in characterizing quantumness of correlations. Inspired by this idea, we will study quantumness of bipartite states arising from different quantum analogs of the classical conditional entropy. Our approach is intrinsic, in contrast to the Olliver–Zurek method that involves extrinsic local measurements. For this purpose, we introduce two alternative variants of quantum conditional entropies via conditional density operators, which in turn are intuitive quantum extensions of equivalent classical expressions for the conditional probability. The significance of these quantum conditional entropies in characterizing quantumness of bipartite states is illustrated through several examples.

By means of a probabilistic coupling technique, we establish some tight upper bounds on the variations of the Tsallis entropies in terms of the uniform distance. We treat both classical and quantum cases. The results provide some quantitative characterizations of the uniform continuity and stability properties of the Tsallis entropies. As direct consequences, we obtain the corresponding results for the Shannon entropy and the von Neumann entropy, which are stronger than the conventional ones.

We establish several inequalities for characteristic functions (Fourier transform of probability densities) in terms of the Fisher information. As applications, we illustrate their significance in estimating the survival probability of a quantum state (Schrodinger wave function). To cite this article: Z. Zhang, C. R. Acad. Sci. Paris, Ser. I 344 (2007).

An inequality which sets an upper bound for characteristic functions (Fourier transform of probabilities) of lattice distributions is established in terms of a discrete version of the Fisher information. Its physical implications for the survival probabilities and lifetime of quantum states are illustrated.

Novel crosslinked porous particles based on the ionic copolymer of 1,1,3,3-tetramethylguanidine acrylate (TMGA) and N,N-methylenebisacrylamide (MBA) were prepared via an inverse suspension polymerization using cyclohexane as continuous phase and Span 60 as the dispersant. The SO 2 absorption-desorption properties of the P(TMGA-co-MBA) particles were studied for the first time. The particles showed excellent SO 2 absorption properties: high capacity and rate. These absorption properties, as well as the particle volume, shape, and morphology, remained unchanged during the SO 2 absorption-desorption cycles. The material appeared to be a good candidate as SO 2 absorbent for fuel gas desulfurization (FGD) and purification of other SO 2 -containing gases.

We study an extremal problem concerning the supremum of the Fourier transforms (characteristic functions) of probability distributions under the constraint that the Fourier transforms vanish at a fixed point. This problem arises from the investigation of the survival amplitudes of quantum states driven by Schrodinger dynamics, and has general and curious implications for the evolution pictures of quantum systems. To cite this article: S. Luo, Z. Zhang, C. R. Acad. Sci. Paris, Ser. I 341 (2005).

The survival amplitude of a quantum state (wave function) under the Schrodinger evolution can be expressed as the Fourier transform of the probability density induced by the wave function in the energy representation. In particular, the first zero of the survival amplitude is a fundamental quantity in characterizing the decaying rate of the quantum state. A basic problem in quantum mechanics is to study how fast the survival amplitude can fall. We present a general estimation of the decaying rate of a quantum state in terms of a moment of any order. The result is established by integrating an inequality which involves controlling trigonometric sums by power functions. This inequality is of independent interest in estimating exponential sums.

Heisenberg's uncertainty relations employ commutators of observables to set fundamental limits on quantum measurement. The information concerning incompatibility (non-commutativity) of observables is well included but that concerning correlation is missing. Schrodinger's uncertainty relations remedy this defect by supplementing the correlation in terms of anti-commutators. However, both Heisenberg's uncertainty relations and Schrodinger's uncertainty relations are expressed in terms of variances, which are not good measures of uncertainty in general situations (e.g., when mixed states are involved). By virtue of the Wigner–Yanase skew information, we will establish an uncertainty relation along the spirit of Schrodinger from a statistical inference perspective and propose a conjecture. The result may be interpreted as a quantification of certain aspect of the celebrated Wigner–Araki–Yanase theorem for quantum measurement, which states that observables not commuting with a conserved quantity cannot be measured exactly.

For a characteristic function (Fourier transform of a probability distribution), the first zero encodes important information. We present a general lower bound estimation of the first zero in terms of a moment of any order. The result proves the complementary nature between the first zero and moments, and has interesting implications for quantum mechanical uncertainty relations. To cite this article: S. Luo, Z. Zhang, C. R. Acad. Sci. Paris, Ser. I 338 (2004).

Entanglement is a manifestation of interference effect, which in turn arises from superposition. Bell's inequalities have their origin in entanglement. Motivated by these observations, we introduce a numerical measure which quantifies entanglement from the interference perspective. It turns out that this measure coincides with Renyi's α -entropy with index α =1/2.

For T ∈ R , T ≠ 0 , let Φ T be the collection of characteristic functions φ such that φ ( T ) = 0 . For t ∈ R define M T ( t ) = sup φ ∈ Φ T | φ ( t ) | . Obviously, M T ( - t ) = M T ( t ) . Luo and Zhang [2005. An extremal problem for Fourier transforms of probabilities. C. R. Math. Acad. Sci. Paris 341, 293–296] found, explicitly, M T ( t ) for | t | ⩽ | T | . In this note it is shown that M T ( t ) = 1 if | t | > | T | , completing the work of Luo and Zhang.

By use of a coupling technique, two inequalities are established which set upper bounds to the mutual information of finite discrete random variables in terms of the Kolmogorov distance (variational distance).

Inspired by the idea of conditional probabilities, we introduce a variant of conditional density operators. But unlike the conditional probabilities which are bounded by 1, the conditional density operators may have eigenvalues exceeding 1 for entangled states. This has the consequence that although any bivariate classical probability distribution has a natural separable decomposition in terms of conditional probabilities, we do not have a quantum analogue of this separable decomposition in general. The ``nonclassical'' eigenvalues of conditional density operators are indications of entanglement. The resulting separability criterion turns out to be equivalent to the reduction criterion introduced by Horodecki [Phys. Rev. A 59, 4206 (1999)] and Cerf et al. [Phys. Rev. A 60, 898 (1999)]. This supplies an intuitive probabilistic interpretation for the reduction criterion. The conditional density operators are also used to define a form of quantum conditional entropy which provides an alternative mechanism to reveal quantum discord.