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基于故障信号频率的识别模型由于受到周围磁场等的影响,精度较低,为提高智能电表电路暂态故障信号实时识别的准确性,从故障信号处理的方向出发,基于时域粗检测方法,研究了一种智能电表电路暂态故障实时识别方法.对智能电表电路故障信号采样,使故障信号按照指定的路线传输,就要增加通道的接收能力,利用小波分析方法,对复杂的电信号进行样本预处理,经过时域检测后的信号被统一进行重新分布,以较为简单的方式进行标记;基于小波熵测度的故障信号融合模型,采用信息熵方法融合分离相似故障信号,确定所有智能电表故障电路信号暂态特征;构建基于小波熵测度的故障信号融合模型,在信号谱上完成信号的筛选与分解,实现智能电表电路暂态故障信号实时识别.实验结果表明,针对智能电表电路接地短路、两相接地短路、相间短路、三相接地短路四种不同类型的暂态故障,通过该方法识别出的故障电压曲线值与实际的值相差小于0.3 V,具有较高的识别准确性,具备一定的实际应用意义. 相似文献
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为了提高多波长光脉冲设备的实用性,采用双波长工作原理,设计了一种稳定的双波长半导体环形光纤激光器。讨论了环形腔色散、滤波器脉宽以及调制深度等对输出脉冲的影响。结果表明,双波长光脉冲的重复率为5.0GHz,典型脉宽为20ps,双波长光脉冲具有良好的边模抑制比,当输出波长为1554.75nm和1557.21nm时,边模抑制比分别为29.1dB和29.7dB,其典型的输出功率分别为-6.7dBm和-6.1dBm,输出光谱的峰值功率波动小于0.5dB。这项研究对太赫兹源和多波长光脉冲设备的研究具有借鉴意义。 相似文献
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The aim of this paper is to characterize representable and weak representable effect algebras and establish a representation theory of effect algebras. An effect algebra E is said to be representable if there exists a Hilbert space H and a monomorphism π from E into the Hilbert space effect algebra ε(H) and it is said to be weakly representable if there exists an injective morphism from E into some ε(H). It is proved that an effect algebra E with the nonempty state space S(E) is representable if and only if x, y ∈ E, f(x)+f(y) ≤ 1 implies x⊕y is defined; it is weakly representable if and only if the state space S(E) separates the points of E. Some operational properties of representable effect algebras are established, and some applications of the obtained results are listed. 相似文献
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We discuss separability of solutions to a Schr?dinger equation that describes a composite quantum system and give some kinds of Hamiltonians H(t) such that the solution to Schr?dinger equation induced by H(t) is separable at any time provided that it is separable at t = 0. For example, we prove that if the Hamiltonian H is time-independent and equals to the product PA■PB of two projections on the subsystems KAand KB, respectively, then the state |ψ(t) of the composite system starting from a separable initial |ψ(0) = |ψA■|ψB is separable for all t ∈ [0, T] if and only if either |ψA is an eigenstate of PA, or |ψB is an eigenstate of PB. 相似文献
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在音频系统中,模拟设备和数字设备通常在一起混合使用,准确的了解掌握和选择一个标准电平,对录音、制作、播出节目信号质量起着重要作用,本文就模拟设备和数字设备的电平如何调控做了阐述。 相似文献
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In this paper we study the stability of(p,Y)-operator frames.We firstly discuss the relations between p-Bessel sequences(or p-frames) and(p,Y)-operator Bessel sequences(or(p,Y)-operator frames).Through defining a new union,we prove that adding some elements to a given(p,Y)-operator frame,the resulted sequence will be still a(p,Y)-operator frame.We obtain a necessary and sufficient condition for a sequence of compound operators to be a(p,Y)operator frame.Lastly,we show that(p,Y)-operator frames for X are stable under some small perturbations. 相似文献