We have developed a simple way to generate binary patterns based on spectral slopes in different frequency ranges at fluctuation-enhanced sensing. Such patterns can be considered as binary "fingerprints" of odors. The method has... more
We have developed a simple way to generate binary patterns based on spectral slopes in different frequency ranges at fluctuation-enhanced sensing. Such patterns can be considered as binary "fingerprints" of odors. The method has experimentally been demonstrated with a commercial semiconducting metal oxide (Taguchi) sensor exposed to bacterial odors (Escherichia coli and Anthrax-surrogate Bacillus subtilis) and processing their stochastic signals. With a single Taguchi sensor, the situations of empty chamber, tryptic soy agar (TSA) medium, or TSA with bacteria could be distinguished with 100% reproducibility. The bacterium numbers were in the range of 2.5 × 10 4-10 6. To illustrate the relevance for ultra-low power consumption, we show that this new type of signal processing and pattern recognition task can be implemented by a simple analog circuitry and a few logic gates with total power consumption in the microWatts range.
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ABSTRACT
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... IN YBaCuO THIN FILMS: SCALING OF FLUCTUATIONS, EXPERIMENTAL EVIDENCE OF PERCOLATION AT THE SUPERCONDUCTING TRANSITION Laszlo B. Kiss*, Peter Svedlindh and Leif Lundgren University of Uppsala ... JW Mantese, WA Curtin Watt W. Webb,... more
... IN YBaCuO THIN FILMS: SCALING OF FLUCTUATIONS, EXPERIMENTAL EVIDENCE OF PERCOLATION AT THE SUPERCONDUCTING TRANSITION Laszlo B. Kiss*, Peter Svedlindh and Leif Lundgren University of Uppsala ... JW Mantese, WA Curtin Watt W. Webb, Phys. Rev. ...
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Time dependent fluctuations of the fraction of normal-conducting part in random resistor-superconductor (RS) and resistor-insulator (RI) networks lead to a novel effect close to the percolation threshold. The normalized noise scales as a... more
Time dependent fluctuations of the fraction of normal-conducting part in random resistor-superconductor (RS) and resistor-insulator (RI) networks lead to a novel effect close to the percolation threshold. The normalized noise scales as a function of the resistance with a characteristic exponent lambda. The value of lambda is different from the value found in classical percolation models but can be related
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The conductivity noises of mirrors yield an amplitude and phase fluctuation of the reflected electromagnetic wave via fluctuations of the complex refractive index of the material. The resultant of the elementary phase fluctuations is... more
The conductivity noises of mirrors yield an amplitude and phase fluctuation of the reflected electromagnetic wave via fluctuations of the complex refractive index of the material. The resultant of the elementary phase fluctuations is calculated by the use of Fresnel's ...
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Ag-Mn nanoparticles were prepared by advanced gas evaporation. Their composition corresponded to Ag0.89Mn0.11, and the particle size distribution was log normal. The particles demonstrated an unambiguous spin glass behavior with the... more
Ag-Mn nanoparticles were prepared by advanced gas evaporation. Their composition corresponded to Ag0.89Mn0.11, and the particle size distribution was log normal. The particles demonstrated an unambiguous spin glass behavior with the temperature dependent magnetic susceptibility displaying a plateau at ~25 K. The magnetic domains were limited by the size of the particles.
Research Interests: Engineering, Applied Physics, Nanocrystalline materials, Nanocrystalline Material, Mathematical Sciences, and 11 morePhysical sciences, Magnetic Susceptibility, Domain wall, Magnetic Domains, Temperature Dependence, Spin Glass, Three Dimensional, Finite Size Effects, Particle Size Distribution, Fine Particles, and Domain Structure
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We introduce a new self-adaptive stochastic resonator system as a simple model for sensing mechanisms. The model is based on a level-crossing detector (LCD) with stepwise, dynamically increasing and relaxing threshold level after each... more
We introduce a new self-adaptive stochastic resonator system as a simple model for sensing mechanisms. The model is based on a level-crossing detector (LCD) with stepwise, dynamically increasing and relaxing threshold level after each firing event. The transfer function is found to be logarithmic-like over a wide range (six decades) of the input signal amplitude. Results on its dynamical response
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... [4] DG Luchinsky and PVE McClintock, Irreversibility of classical fluctuations studied in analogue electrical circuits, Nature 389 (1997), p. 463. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (70). [5] SM... more
... [4] DG Luchinsky and PVE McClintock, Irreversibility of classical fluctuations studied in analogue electrical circuits, Nature 389 (1997), p. 463. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (70). [5] SM Bezrukov and I. Vodyanoy, Stochastic resonance in non ...
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The results of UV laser ablation of gold nanoparticle films on glass substrates using femtosecond pulses are presented. Films of ultra-fine gold particles were prepared by an inert gas evaporation and deposition technique, resulting in a... more
The results of UV laser ablation of gold nanoparticle films on glass substrates using femtosecond pulses are presented. Films of ultra-fine gold particles were prepared by an inert gas evaporation and deposition technique, resulting in a well-defined log-normal particle size distribution of (7&#451) nm. The pulse length of the laser was 500 fs at a wavelength of 248 nm. Ablation
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... [4] DG Luchinsky and PVE McClintock, Irreversibility of classical fluctuations studied in analogue electrical circuits, Nature 389 (1997), p. 463. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (70). [5] SM... more
... [4] DG Luchinsky and PVE McClintock, Irreversibility of classical fluctuations studied in analogue electrical circuits, Nature 389 (1997), p. 463. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (70). [5] SM Bezrukov and I. Vodyanoy, Stochastic resonance in non ...
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Stochastic resonator systems with input and/or output 1/f noise have been studied. Disordered magnets/dielectrics serve as examples for the case of output 1/f noise with white noise (thermal excitation) at the input of the resonators. Due... more
Stochastic resonator systems with input and/or output 1/f noise have been studied. Disordered magnets/dielectrics serve as examples for the case of output 1/f noise with white noise (thermal excitation) at the input of the resonators. Due to the fluctuation-dissipation theorem, the output noise is related to the out-of-phase component of the periodic peak of the output spectrum. Spin glasses and ferromagnets serve as interesting examples of coupled stochastic resonators. A proper coupling can lead to an extremely large signal-to- ...
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We generalize the model of self-organized critical systems to cases where due to some internal degrees of freedom the local conservation law is violated. This can be realized by taking a transfer ratio different from the critical one in a... more
We generalize the model of self-organized critical systems to cases where due to some internal degrees of freedom the local conservation law is violated. This can be realized by taking a transfer ratio different from the critical one in a sand pile model (global violation) or allowing fluctuations around the critical ratio (local violation). In the first case the deviation from the critical ratioR is a critical parameter and the characteristic avalanche size diverges as| R|-?. In the second case the global conservation assures criticality; however, our ...
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Abstract. The explanation of I/f noise with the help of models of self-organised criticality makes use of combining scaling and the distributed time-constant picture. Limits of applicability of this type of arguments are presented. The... more
Abstract. The explanation of I/f noise with the help of models of self-organised criticality makes use of combining scaling and the distributed time-constant picture. Limits of applicability of this type of arguments are presented. The numerical study of the twodimensional model of Bak, Tang and Wiesenfeld shows that although non-trivial scaling is present, the power spectrum of the total process has al/f2 behaviour.
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... The signal transduction is done by a novel, continuous-time detector circuit followed by a low-noise lock-in architec-ture which measures the admittance of the sensor as a function of frequency for BDS. ... The dimension of the... more
... The signal transduction is done by a novel, continuous-time detector circuit followed by a low-noise lock-in architec-ture which measures the admittance of the sensor as a function of frequency for BDS. ... The dimension of the capacitor enables trapping of single bio-molecules. ...
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ABSTRACT A CMOS sensor array IC capable of performing fluctuation enhanced sensing for two different chemical sensing devices has been designed. The targeted sensing devices are the novel Van der Waals force enhanced MOSFET for gas and... more
ABSTRACT A CMOS sensor array IC capable of performing fluctuation enhanced sensing for two different chemical sensing devices has been designed. The targeted sensing devices are the novel Van der Waals force enhanced MOSFET for gas and nano-particle detection and sputtered ZnO thin films as Taguchi-type sensors for gas detection. The sensor output contains information in the dynamic stochastic fluctuations around the mean value which prove useful for detection of sub-ppm concentrations of gaseous molecules. This paper discusses an implementation of fluctuation-enhanced sensing on silicon. The CMOS sensor IC consists of a low-noise transimpedance amplifier filter bank and output buffers. The circuits are all designed to operate at temperatures as high as 200°C with low leakage currents. The overall CMOS system on chip exhibited enhanced selectivity and accuracy in providing unique signatures for gas detection.
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Both selectivity and sensitivity of chemical sensors can be significantly improved by exploiting the information contained in microfluctuations present in the sensor system. We call our collection of methods to extract information from... more
Both selectivity and sensitivity of chemical sensors can be significantly improved by exploiting the information contained in microfluctuations present in the sensor system. We call our collection of methods to extract information from these microfluctuations Fluctuation-Enhanced Sensing (FES). In this review paper we discuss general FES principles and two types of applications; gas sensing with commercial solid state sensors and the Sensing of Phage-Triggered Ion Cascde (SEPTIC) technique to detect and identify bacteria.
ABSTRACT Nanoparticle films of crystalline WO3, designed for gas sensing applications, were deposited on alumina substrates by reactive gas deposition. H2S, ethanol vapour, and binary mixtures of ethanol/H2S, ethanol/NO2 and H2S/NO2 were... more
ABSTRACT Nanoparticle films of crystalline WO3, designed for gas sensing applications, were deposited on alumina substrates by reactive gas deposition. H2S, ethanol vapour, and binary mixtures of ethanol/H2S, ethanol/NO2 and H2S/NO2 were used in different concentrations for testing the performance of the sensor device. The sensor was operated in dynamic mode by modulating its temperature between 150 and 250 °C. Coefficients were extracted by applying Fast Fourier Transform (FFT) and Discrete Wavelet Transform (DWT) methods to the dynamic resistance response of the sensor. These coefficients were then used as inputs for pattern recognition methods to extract both quantitative (concentration) and qualitative (chemical selectivity) information about the test gases. After sensor calibration, it was possible to detect as little as 200 ppb of ethanol and 20 ppb of H2S with good accuracy. Furthermore, ethanol and H2S could be detected with good sensitivity and selectivity in the presence of both reducing and oxidising gases.
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We present introductory considerations and analysis toward computing applications based on the recently introduced deterministic logic scheme with random spike (pulse) trains [Phys. Lett. A373 (2009) 2338–2342]. Also, in considering the... more
We present introductory considerations and analysis toward computing applications based on the recently introduced deterministic logic scheme with random spike (pulse) trains [Phys. Lett. A373 (2009) 2338–2342]. Also, in considering the questions, "why random?" and "why pulses?", we show that the random pulse based scheme provides the advantages of realizing multivalued deterministic logic. Pulse trains are realized by an element called orthogonator. We discuss two different types of orthogonators, parallel (intersection-based) and serial (demultiplexer-based) orthogonators. The last one can be slower but it makes sequential logic design straightforward. We propose generating a multidimensional logic hyperspace [Phys. Lett. A373 (2009) 1928–1934] by using the zero-crossing events of uncorrelated Gaussian electrical noises available in the chips. The spike trains in the hyperspace are non-overlapping, and are referred to as neuro-bits. To demonstrate this idea, we...
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In this Letter, we propose a simple method to strongly enhance the sensitivity of the detection of the new technique called "SEnsing of Phage-Triggered Ion Cascade (SEPTIC)". The method accumulates those phage infected bacteria... more
In this Letter, we propose a simple method to strongly enhance the sensitivity of the detection of the new technique called "SEnsing of Phage-Triggered Ion Cascade (SEPTIC)". The method accumulates those phage infected bacteria which are emitting ions and releases those which have stopped the ion emission activity. The estimated increasing of the sensitivity can reach several orders of magnitude at practical conditions.
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In Zeng et al. [Fluct. Noise Lett. 7 (2007) L439–L447] the analysis of the lowest unique positive integer game is simplified by some reasonable assumptions that make the problem tractable for arbitrary numbers of players. However, here we... more
In Zeng et al. [Fluct. Noise Lett. 7 (2007) L439–L447] the analysis of the lowest unique positive integer game is simplified by some reasonable assumptions that make the problem tractable for arbitrary numbers of players. However, here we show that the solution obtained for rational players is not a Nash equilibrium and that a rational utility maximizer with full computational capability would arrive at a solution with a superior expected payoff. An exact solution is presented for the three- and four-player cases and an approximate solution for an arbitrary number of players.