36,469 research outputs found

    Low-Voltage High-Linearity Wideband Current Differencing Transconductance Amplifier and Its Application on Current-Mode Active Filter

    Get PDF
    A low-voltage high-linearity wideband current differencing transconductance amplifier (CDTA) is presented in this paper. The CDTA consists of a current differencing circuit and a cross-coupling transconductance circuit. The PSPICE simulations of the proposed CDTA show a good performance: -3dB frequency bandwith is about 900 MHz, low power consumption is 2.48 mW, input current linear range is ±100 µA and low current-input resistance is less than 20 Ω, high current-output resistance is more than 3 MΩ. PSpice simulations for a current-mode universal filter and a proposed high-order filter are also conducted, and the results verify the validity of the proposed CDTA

    Generation of GHZ and W states for stationary qubits in spin network via resonance scattering

    Full text link
    We propose a simple scheme to establish entanglement among stationary qubits based on the mechanism of resonance scattering between them and a single-spin-flip wave packet in designed spin network. It is found that through the natural dynamical evolution of an incident single-spin-flip wave packet in a spin network and the subsequent measurement of the output single-spin-flip wave packet,multipartite entangled states among n stationary qubits, Greenberger-Horne-Zeilinger (GHZ) and W states can be generated.Comment: 8 pages, 6 figure

    Topological Weyl and Node-Line Semimetals in Ferromagnetic Vanadium-Phosphorous-Oxide β\beta-V2_2OPO4_4 Compound

    Full text link
    We propose that the topological semimetal features can co-exist with ferromagnetic ground state in vanadium-phosphorous-oxide β\beta-V2_2OPO4_4 compound from first-principles calculations. In this magnetic system with inversion symmetry, the direction of magnetization is able to manipulate the symmetric protected band structures from a node-line type to a Weyl one in the presence of spin-orbital-coupling. The node-line semimetal phase is protected by the mirror symmetry with the reflection-invariant plane perpendicular to magnetic order. Within mirror symmetry breaking due to the magnetization along other directions, the gapless node-line loop will degenerate to only one pair of Weyl points protected by the rotational symmetry along the magnetic axis, which are largely separated in momentum space. Such Weyl semimetal phase provides a nice candidate with the minimum number of Weyl points in a condensed matter system. The results of surface band calculations confirm the non-trivial topology of this proposed compound. This findings provide a realistic candidate for the investigation of topological semimetals with time-reversal symmetry breaking, particularly towards the realization of quantum anomalous Hall effect in Weyl semimetals.Comment: 5 pages, 4 figure

    Effect and Compensation of Timing Jitter in Through-Wall Human Indication via Impulse Through-Wall Radar

    Get PDF
    Impulse through-wall radar (TWR) is considered as one of preferred choices for through-wall human indication due to its good penetration and high range resolution. Large bandwidth available for impulse TWR results in high range resolution, but also brings an atypical adversity issue not substantial in narrowband radars — high timing jitter effect, caused by the non-ideal sampling clock at the receiver. The fact that impulse TWR employs very narrow pulses makes little jitter inaccuracy large enough to destroy the signal correlation property and then degrade clutter suppression performance. In this paper, we focus on the timing jitter impact on clutter suppression in through-wall human indication via impulse TWR. We setup a simple timing jitter model and propose a criterion namely average range profile (ARP) contrast is to evaluate the jitter level. To combat timing jitter, we also develop an effective compensation method based on local ARP contrast maximization. The proposed method can be implemented pulse by pulse followed by exponential average background subtraction algorithm to mitigate clutters. Through-wall experiments demonstrate that the proposed method can dramatically improve through-wall human indication performance

    The second phase transition in the pyrochlore oxide Cd2Re2O7

    Full text link
    Evidence for another phase transition at 120 K in the metallic pyrochlore oxide Cd2Re2O7, following the structural transition at 200 K and followed by the superconducting transition at 1.0 K, is given through resistivity, magnetoresistance, specific heat, and X-ray diffraction measurements. The results indicate unique successive structural and electronic transitions occurring in the pyrochlore compound, revealing an interesting interplay between the crystal and electronic structures on the itinerant electron system in the pyrochlore lattice

    The relationship between innovation culture and innovation outcomes: exploring the effects of sustainability orientation and firm size

    Get PDF
    Being sustainability oriented has become a key strategy for many firms. Equally, innovation culture and innovation outcomes have long been recognized as important contributors to the growth of firms. However, the literature on sustainability and innovation provides limited understanding of the important relationship between sustainability orientation, innovation culture and innovation outcomes. Given that large firms and small firms differ in building and employing their strategic assets, firm size matters in understanding the relationship. Through the lens of resource-based view, we develop a theoretical model embedding the four components and test it using data from a global survey: the 2012 Comparative Performance Assessment Study. Our research contributes to sustainability literature and innovation theory by providing an integrated framework to explicate the mechanism through which the innovation culture of the firm impacts on innovative performance through the sustainability orientation of the firm. The findings advance our understanding of the extent to which sustainable orientation can explain the relationship between innovation culture and innovation outcomes. Our evidence shows that the innovation culture of a firm facilitates the sustainability orientation of the firm and that the converse also applies. The research also contributes to our knowledge of the differences between large and small firms in leveraging their strategic assets in terms of innovation culture and sustainability orientation to facilitate superior innovation outcomes. Although firm size moderates the relationship between innovation culture and innovation outcomes, the research shows that this no longer holds when sustainability orientation is included in the relationship. A strong sustainability orientation can be a competitive advantage for firms in the delivery of superior innovation outcomes
    corecore