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91.
The central contribution of the current paper is to establish a practical and effective reusable garbled circuit scheme with parallel updates, where each update is applied to the circuit in parallel. First of all, we present a strengthened notion of inner product functional encryption (IPE) called simulation-based security (SIM-security) for multi-instance and show that a secret-key IPE scheme is multi-instance SIM-secure. Then we put forward a reusable garbled circuit scheme based on the IPE scheme. The idea is a reduction from re-randomizable garbled circuits in which the distribution of the original garbled circuit is computationally indistinguishable from the re-randomized garbled circuit. Finally, we implemented reusable garbled circuits and validate the practicality of our reusable garbled circuit scheme. Experimental results demonstrate that our reusable garbled circuit scheme is suitable for a wide range of real-world scenarios. 相似文献
92.
Contactless readout of passive LC sensors composed of a capacitance sensor connected to a coil can be performed through a readout coil electromagnetically coupled with the sensor coil. Resonant frequency and quality factor can be extracted from the impedance measured at the readout coil by a technique which results theoretically independent of the coupling, and, therefore, the distance between the readout and the sensor coils. However, the effect of the unavoidable parasitic capacitance connected to the readout coil introduces in practice an undesired dependence of the measured values on the distance between the coils, resulting in a decreased accuracy. In this paper, such dependence is predicted by the results of a numerical analysis and experimentally verified. To overcome this limitation, a novel electronic technique and circuit topology for the compensation of the readout parasitic capacitance is proposed. The experimental results show that the compensation technique allows to read the resonant frequency of a LC pair at around 5.3 MHz with a variation of less than 200 ppm across an interrogation distance between 2 and 24 mm. 相似文献
93.
将超声珩齿加工变幅杆和被加工齿轮组成的超声振动系统简化为变幅器,基于圆锥形变幅杆和环盘(被加工齿轮)组成变幅器的频率方程,导出齿轮半径、厚度变化对谐振频率的影响,以及变幅杆的调整规律,并运用有限元分析的方法对设计结果进行了验证,从而为变幅杆及工作频率的设计选择提供了依据。 相似文献
94.
有源噪声控制次级声源的非线性建模 总被引:1,自引:0,他引:1
基于电动扬声器的顺性、磁力因子和音圈自感三个非线性参数,建立了基于电力声类比线路方法的次级声源非线性时域模型.采用该模型对次级声源总谐波失真(THD)进行仿真,并与测试结果进行比较,结果表明在较低频率范围、较大输入信号幅值的情况下,该非线性模型是可行的.将该模型引入有源噪声控制系统,并以滤波-XLMS算法为例,对采用次级声源理想模型、线性时域模型和非线性时域模型的控制系统分别进行仿真,结果表明采用非线性模型系统的降噪量远低于采用其他模型的系统,并且非线性失真度大小对降噪量也具有明显的影响. 相似文献
95.
Winai Jaikla 《Microelectronics Journal》2011,42(1):135-140
This paper presents a new realization of resistorless mixed-mode (i.e. both voltage-mode and current-mode) quadrature sinusoidal oscillator using a new active building block (ABB) called the differential voltage current-controlled conveyor transconductance amplifier (DVCCCTA). The proposed oscillator circuit uses a single DVCCCTA, two grounded capacitors (GCs) and does not employ any external linear resistors. The tuning laws for the condition of oscillation (CO) and the frequency of oscillation (FO) are non-interactive; and controlled by separate bias currents. The circuit provides two explicit quadrature current outputs and two quadrature voltage outputs and thus can be classified as a mixed-mode quadrature oscillator. Another notable feature of the proposed circuit is that it can also be used as a biquadratic filter to realize low-pass and band-pass filtering functions simultaneously. Non-ideal analysis of the circuit is provided and PSpice simulation results have been included to verify the workability of the proposed circuit. 相似文献
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97.
该文主要设计了一种用于AC-DC电源管理芯片中的频率为100khz的可修条高精度振荡器,它以比较器为核心电路,并利用系统内部产生的恒流源对电容进行充放电,经过控制电路的作用后,使输出波形为线性度很好的三角波。通过HSPICE的仿真结果表明,三角波具有较好的线性度,其信号振荡频率随电源电压和温度的波动变化较小,性能良好,... 相似文献
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