Enhanced logical stochastic resonance under periodic forcing

It was demonstrated recently that noise in an optimal window allows a bistable system to operate reliably as reconfigurable logic gates (Murali et al., 2009) [1], as well as a memory device (Kohar and Sinha, 2012) [11]. Namely, in a range of moderate noise, the system can operate flexibly, both as a NAND/AND/OR/NOR gate and a Set Reset latch. Here we demonstrate how the width of the optimal noise window can be increased by utilizing the constructive interplay of noise and periodic forcing, namely noise in conjunction with a periodic drive yields consistent logic outputs for all noise strengths below a certain threshold. Thus we establish that in scenarios where noise level is below the minimum threshold required for logical stochastic resonance (or stochastic resonance in general), we can add a periodic forcing to obtain the desired effects. Lastly, we also show how periodic forcing reduces the switching time, leading to faster operation of devices and lower latency effects.     

Two-Parameter Stochastic Resonance in a Model of Electrodissolution of Fe in H_2SO_4

IntroductionStochastic resonance (SR) is a nonlinear effect which describes the optimal detection of a weak periodic signal by the action of external noise in nonlinear systems. SR was originally proposed to account for periodicity in the Earth's ice ages1, and it has been observed in a wide range of biological2-4 , physical5 and chemical6 systems. The systems mentioned above which may give rise to SR have a denominator despite many examples of SR in different scientific areas. It is noted…     

Optimizing the thulium doped fiber amplifier (TDFA) gain and noise figure for S-band 16 × 10 Gb/s WDM systems

This paper aims to evaluate a comprehensive numerical model based on solving rate equations of a thulium-doped silica-based fiber amplifier. The pump power and thulium-doped fiber (TDF) length for single-pass thulium-doped fiber amplifiers (TDFA) are theoretically optimized to achieve the optimum gain and noise figure (NF) at the center of S-band region. The 1064 nm pump is used to provide both ground-state and excited state absorptions for amplification in the S-band region. The theoretical result is in agreement with the published experimental result.     

A new method for removing impulse noise based on noise space characteristic

This paper proposes a new method for eliminating impulse noise. Based on the space characteristic of object and noise, three kinds of basic noise patterns are introduced to describe noise and detect noise candidates. Correspondingly, noise removal operators are presented to remove the impulse noise. Extensive experiment results have shown that the proposed method is better than some of the state-of-the-art methods.     

风机封闭系统内噪声模拟分析

风机系统工作时的一个突出问题是其进风口和出风口产生的噪声。由于风机流场非常复杂,以及实验成本、实验条件限制,基于计算流体力学（Computational Fluid Dynamics, CFD）的理论逐渐成为风机噪声估计的重要方法。本文拟通过对由风机及其冷却系统构成的封闭系统进行数值建模和仿真,判断出风机主要气动噪声源的位置和种类,为处于封闭系统内的风机的噪声大小预测,提供一个可供参考的信息。结果表明：风机出口腔体内部非定常压力波动强度最大。     

基于DEMON线谱的轴频提取方法研究

目标的螺旋桨不同则轴频不相同。轴频是目标的特征之一,可以应用于目标识别当中。本文提出一种改进的高频噪声解调分析(DEMON)方法,能够得到具有明显线谱的DEMON谱;提出最大公约数算法,并给出提取轴频的具体步骤。海试数据实验结果验证了本文所提方法及算法的有效性和可行性。     

Marked signal improvement by stochastic resonance for aperiodic signals in the double-well system

On the basis of our mixed-signal simulations we report significant stochastic resonance induced input-output signal improvement in the double-well system for aperiodic input types. We used a pulse train with randomised pulse locations and a band-limited noise with low cut-off frequency as input signals, and applied a cross-spectral measure to quantify their noise content. We also supplemented our examinations with simulations in the Schmitt trigger to show that the signal improvement we obtained is not a result of a potential filtering effect due to the limited response time of the double-well dynamics.     

The changing role of physical testing in vehicle development programmes

The role of physical testing in product development is changing due to the requirements for faster new product development, reduced tolerance of failures in the field and the emergence of computer aided engineering (CAE) technologies. To be used most effectively, testing must be seen as an integral part of the process for reducing risks associated with new product introductions. Quality function deployment (QFD) and failure modes and effects analysis (FMEA) can be used to establish effective test and development plans that integrate the use of virtual and physical testing. By effectively integrating virtual and physical test technologies significant improvements in product performance can be achieved within shorter times and with reduced development and manufacturing costs. The approach was illustrated by a process of reducing in-cab noise during the design of a new truck.     

Generation of burst noise by nonlinear autoregression

Nonlinear generalization of autoregressive sequence of first order is used as basis for construction of mathematical model of bistable burst noise. It is proved that the noise generated using such a model has Lorentzian spectrum after clipping the white noise component. In passing it is demonstrated that random telegraph signal is obtainable by simple iteration. The proposed model suggests that one should expect to observe temperature dependence of frequency of transitions between the two levels of burst noise waveform.