### 25677 results for qubit oscillator frequency

Contributors: M.R. Qader

Date: 2013-01-01

ORIGINAL ARTICLE - Detuning effects in Haar wavelet spectrum of pulsed-driven **qubit**...Driven **qubit**...The transient scattered radiation due to interaction of a short laser pulse (of rectangular shape) with a **qubit** is studied through the Haar wavelet window spectrum. Asymmetrical structure in the spectrum is shown due to **frequency** miss-match of the laser and **qubit** **frequencies** and the shift window parameter. ... The transient scattered radiation due to interaction of a short laser pulse (of rectangular shape) with a **qubit** is studied through the Haar wavelet window spectrum. Asymmetrical structure in the spectrum is shown due to **frequency** miss-match of the laser and **qubit** **frequencies** and the shift window parameter.

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Contributors: Hung-Chun Chien, Chih-Yen Chen

Date: 2014-02-01

Circuit diagram of the proposed DVCCTA-based variable** frequency** dual-mode sinusoidal oscillator.
...Simulation results of the current output Io for the variable** frequency** dual-mode sinusoidal oscillator (Fig. 4): (a) output waveform in the steady state** and (b) **the corresponding** frequency** spectrum.
...Simulation results of the current output Io for the single-resistance-controlled dual-mode sinusoidal oscillator (Fig. 3): (a) output waveform in the steady state** and (b) **corresponding** frequency** spectrum.
...**Oscillation** **frequency** against the bias current IB of the circuit shown in Fig. 4.
...CMOS realization of single-resistance-controlled and variable **frequency** dual-mode sinusoidal **oscillators** employing a single DVCCTA with all-grounded passive components...Sinusoidal **oscillator**...In this paper, two new designs are proposed for sinusoidal **oscillators** based on a single differential voltage current conveyor transconductance amplifier (DVCCTA). Each of the proposed circuits comprises a DVCCTA combined with passive components that simultaneously provides both voltage and current outputs. The first circuit is a DVCCTA-based single-resistance-controlled **oscillator** (SRCO) that provides independent control of the **oscillation** condition and **oscillation** **frequency** by using distinct circuit parameters. The second circuit is a DVCCTA-based variable **frequency** **oscillator** (VFO) that can provide independent control of the **oscillation** **frequency** by adjusting the bias current of the DVCCTA. In this paper, the DVCCTA and relevant formulations of the proposed **oscillator** circuits are first introduced, followed by the non-ideal effects, sensitivity analyses, **frequency** stability discussions, and design considerations. After using the 0.35-μm CMOS technology of the Taiwan Semiconductor Manufacturing Company (TSMC), the HSPICE simulation results confirmed the feasibility of the proposed **oscillator** circuits....Simulation results of the start-up **oscillations** of the variable **frequency** dual-mode sinusoidal **oscillator** (Fig. 4).
...In this paper, two new designs are proposed for sinusoidal **oscillators** based on a single differential voltage current conveyor transconductance amplifier (DVCCTA). Each of the proposed circuits comprises a DVCCTA combined with passive components that simultaneously provides both voltage and current outputs. The first circuit is a DVCCTA-based single-resistance-controlled **oscillator** (SRCO) that provides independent control of the oscillation condition and oscillation **frequency** by using distinct circuit parameters. The second circuit is a DVCCTA-based variable **frequency** **oscillator** (VFO) that can provide independent control of the oscillation **frequency** by adjusting the bias current of the DVCCTA. In this paper, the DVCCTA and relevant formulations of the proposed **oscillator** circuits are first introduced, followed by the non-ideal effects, sensitivity analyses, **frequency** stability discussions, and design considerations. After using the 0.35-μm CMOS technology of the Taiwan Semiconductor Manufacturing Company (TSMC), the HSPICE simulation results confirmed the feasibility of the proposed **oscillator** circuits....Circuit diagram of the proposed DVCCTA-based variable **frequency** dual-mode sinusoidal **oscillator**.
...Simulation results of the voltage **output Vo** for the variable** frequency** dual-mode sinusoidal oscillator (Fig. 4): (a) output waveform in the steady state** and (b) **the corresponding** frequency** spectrum.
...Variation of the **oscillation** **frequency** against R2 for the circuit (Fig. 3).
...Simulation results of the start-up oscillations of the variable** frequency** dual-mode sinusoidal oscillator (Fig. 4).
...Simulation results of the highest applicable **oscillations** of the variable **frequency** dual-mode sinusoidal **oscillator** (Fig. 4): (a) output waveform in the steady state; and (b) the start-up of the **oscillations**.
... In this paper, two new designs are proposed for sinusoidal **oscillators** based on a single differential voltage current conveyor transconductance amplifier (DVCCTA). Each of the proposed circuits comprises a DVCCTA combined with passive components that simultaneously provides both voltage and current outputs. The first circuit is a DVCCTA-based single-resistance-controlled **oscillator** (SRCO) that provides independent control of the **oscillation** condition and **oscillation** **frequency** by using distinct circuit parameters. The second circuit is a DVCCTA-based variable **frequency** **oscillator** (VFO) that can provide independent control of the **oscillation** **frequency** by adjusting the bias current of the DVCCTA. In this paper, the DVCCTA and relevant formulations of the proposed **oscillator** circuits are first introduced, followed by the non-ideal effects, sensitivity analyses, **frequency** stability discussions, and design considerations. After using the 0.35-μm CMOS technology of the Taiwan Semiconductor Manufacturing Company (TSMC), the HSPICE simulation results confirmed the feasibility of the proposed **oscillator** circuits.

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Contributors: Václav Tesař

Date: 2014-01-01

Geometry of the diverter valve of the discussed oscillator in its initial design. Very similar – but not identical – to the design in the preliminary model, shown in Fig. 8.
...Depend...Measured **oscillation** **frequency** with different feedback tube lengths of the **oscillator** shown in Fig. 7, plotted as a function of the supplied flow rate. Surprisingly, the **frequency** is neither proportional to the flow rate (as is usual in the constant Strouhal-number **oscillators**, e.g., Tesař et al., 2006) – nor constant (as in the **oscillators** with resonator channel (Tesař et al., 2013)).
...Photograph of internal cavities of the integrated oscillator/aerator as used in the final experiments aimed at achieving high oscillation frequency. Note the absence of the “island” components as they are discussed in association with Figs. 5 and 11.
...Fluidic **oscillator**...Comparison of the oscillation in Fig. 17 and the basic frequency component L in Fig. 23. The replacement of the feedback channel loops by open areas for vortical flow made the feedback paths slightly shorter (and therefore the frequency higher).
...Results of measured dependence of **oscillation** **frequency** on the supplied flow rate in the layout shown in Figs. 20 and 12. Apart from basic **frequency** L, the output spectrum exhibited a much higher **frequency** component H.
...**Frequency** of generated **oscillation** plotted as a function of the air flow rate. Similarly as in Fig. 9 this dependence does not the fit the usual (constant Strouhal number) proportionality between **frequency** and flow rate.
...Measured oscillation frequency with different feedback tube lengths of the oscillator shown in Fig. 7, plotted as a function of the supplied flow rate. Surprisingly, the frequency is neither proportional to the flow **rate (as is** usual in the constant Strouhal-number oscillators, e.g., Tesař et al., 2006) – nor constant (as in the oscillators with resonator channel (Tesař et al., 2013)).
...Comparison of the oscillation in Fig. 17 and the basic **frequency** component L in Fig. 23. The replacement of the feedback channel loops by open areas for vortical flow made the feedback paths slightly shorter (and therefore the **frequency** higher)....Basic data on the geometry of the **oscillator** used in the high-**frequency** experiments.
...Microbubble generator excited by fluidic **oscillator's** third harmonic **frequency**...Comparison of the **oscillation** in Fig. 17 and the basic **frequency** component L in Fig. 23. The replacement of the feedback channel loops by open areas for vortical flow made the feedback paths slightly shorter (and therefore the **frequency** higher)....Efficient generation of sub-millimetre microbubbles was recently made possible by pulsating the flow of gas supplied into a parallel-exits aerator, using a fluidic **oscillator** for the purpose. Without moving parts, it can generate **oscillation** at high **frequency**, an important factor due to bubble natural **frequency** rapidly increasing with the desirable decrease of their size. This paper discusses development of an unusual **oscillator** – a part of an integral **oscillator**/aerator unit – capable of generating a particularly high driving **frequency**, in the kilohertz range, in a layout that promotes a strong third harmonic **frequency** of the basic **oscillation**....Detail photograph of the feedback channel entrances with the added sharp-edged “noses”.
...Efficient generation of sub-millimetre microbubbles was recently made possible by pulsating the flow of gas supplied into a parallel-exits aerator, using a fluidic **oscillator** for the purpose. Without moving parts, it can generate oscillation at high **frequency**, an important factor due to bubble natural **frequency** rapidly increasing with the desirable decrease of their size. This paper discusses development of an unusual **oscillator** – a part of an integral **oscillator**/aerator unit – capable of generating a particularly high driving **frequency**, in the kilohertz range, in a layout that promotes a strong third harmonic **frequency** of the basic oscillation....Dependence of bubble natural **oscillation** **frequency** on the size – based on the measurements in Tesař (2013b). The line is fitted for constant value of **oscillation** Weber number We0.
... Efficient generation of sub-millimetre microbubbles was recently made possible by pulsating the flow of gas supplied into a parallel-exits aerator, using a fluidic **oscillator** for the purpose. Without moving parts, it can generate **oscillation** at high **frequency**, an important factor due to bubble natural **frequency** rapidly increasing with the desirable decrease of their size. This paper discusses development of an unusual **oscillator** – a part of an integral **oscillator**/aerator unit – capable of generating a particularly high driving **frequency**, in the kilohertz range, in a layout that promotes a strong third harmonic **frequency** of the basic **oscillation**.

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Contributors: George F. Beard, Michael J. Griffin

Date: 2014-01-01

Roll transmissibility of the foam cushion during exposure to roll **oscillation** and roll-compensated lateral **oscillation** at 0.1, 0.2, and 0.4 m s−2 r.m.s. at **frequencies** from 0.25 to 1.0 Hz. Median values from 20 subjects.
...Comparison of equivalent comfort contours for lateral oscillation on rigid and cushioned seats without a backrest and the reciprocals of the asymptotic and the realisable versions of frequency weighting Wd for lateral acceleration (BS 6841, 1987). Contours for rigid seats normalised to unity at 1 Hz.
...Root-sums-of-squares of **frequency**-weighted measured components at the seat-body interface during lateral **oscillation**, roll **oscillation**, and fully roll-compensated lateral **oscillation** on a rigid seat and on a foam cushion. Components weighted using axis multiplying factors and asymptotic weightings extrapolated horizontally at **frequencies** less than 0.5 Hz without band-pass filtering (BS 6841, 1987). Median values from 20 subjects.
...Comparison of equivalent comfort contours for roll oscillation on rigid and cushioned seats without a backrest and the reciprocals of the asymptotic and the realisable versions of frequency weighting We for roll acceleration (BS 6841, 1987). Contours normalised to unity at 1 Hz.
...The discomfort caused by lateral oscillation, roll oscillation, and fully roll-compensated lateral oscillation has been investigated at **frequencies** between 0.25 and 1.0 Hz when sitting on a rigid seat and when sitting on a compliant cushion, both without a backrest. Judgements of vibration discomfort and the transmission of lateral and roll oscillation through the seat cushion were obtained with 20 subjects. Relative to the rigid seat, the cushion increased lateral acceleration and roll oscillation at the lower **frequencies** and also increased discomfort during lateral oscillation (at **frequencies** less than 0.63 Hz), roll oscillation (at **frequencies** less than 0.4 Hz), and fully roll-compensated lateral oscillation (at **frequencies** between 0.315 and 0.5 Hz). The root-sums-of-squares of the **frequency**-weighted lateral and roll acceleration at the seat surface predicted the greater vibration discomfort when sitting on the cushion. The **frequency**-dependence of the predicted discomfort may be improved by adjusting the **frequency** weighting for roll acceleration at **frequencies** between 0.25 and 1.0 Hz....The discomfort caused by lateral **oscillation**, roll **oscillation**, and fully roll-compensated lateral **oscillation** has been investigated at **frequencies** between 0.25 and 1.0 Hz when sitting on a rigid seat and when sitting on a compliant cushion, both without a backrest. Judgements of vibration discomfort and the transmission of lateral and roll **oscillation** through the seat cushion were obtained with 20 subjects. Relative to the rigid seat, the cushion increased lateral acceleration and roll **oscillation** at the lower **frequencies** and also increased discomfort during lateral **oscillation** (at **frequencies** less than 0.63 Hz), roll **oscillation** (at **frequencies** less than 0.4 Hz), and fully roll-compensated lateral **oscillation** (at **frequencies** between 0.315 and 0.5 Hz). The root-sums-of-squares of the **frequency**-weighted lateral and roll acceleration at the seat surface predicted the greater vibration discomfort when sitting on the cushion. The **frequency**-dependence of the predicted discomfort may be improved by adjusting the **frequency** weighting for roll acceleration at **frequencies** between 0.25 and 1.0 Hz....Lateral transmissibility of the foam cushion during exposure to lateral **oscillation**, roll **oscillation**, and fully roll-compensated lateral **oscillation** at 0.1, 0.2, and 0.4 m s−2 r.m.s. at **frequencies** from 0.25 to 1.0 Hz. Median values from 20 subjects.
...Effect of magnitude of **oscillation** on the roll velocity measured at the seat-body interface with the foam cushion during exposure to lateral **oscillation** and roll **oscillation** at **frequencies** between 0.25 and 1.0 Hz. Median values from 20 subjects.
...Lateral transmissibility of the foam cushion during exposure to lateral oscillation, roll oscillation, and fully roll-compensated lateral oscillation at 0.1, 0.2, and 0.4 m s−2 r.m.s. at frequencies from 0.25 to 1.0 Hz. Median values from 20 subjects.
...Roll transmissibility of the foam cushion during exposure to roll oscillation and roll-compensated lateral oscillation at 0.1, 0.2, and 0.4 m s−2 r.m.s. at frequencies from 0.25 to 1.0 Hz. Median values from 20 subjects.
...Root-sums-of-squares of frequency-weighted measured components at the seat-body interface during lateral oscillation, roll oscillation, and fully roll-compensated lateral oscillation on a rigid seat and on a foam cushion. Components weighted using axis multiplying factors and asymptotic weightings extrapolated horizontally at frequencies less than 0.5 Hz without band-pass filtering (BS 6841, 1987). Median values from 20 subjects.
...Discomfort of seated persons exposed to low **frequency** lateral and roll oscillation: Effect of seat cushion...Percentages of subjects reporting discomfort localised at the ischial tuberosities when sitting on the rigid seat and on the foam cushion during exposure to lateral **oscillation**, roll **oscillation**, and fully roll-compensated lateral **oscillation** across all **frequencies**.
... The discomfort caused by lateral **oscillation**, roll **oscillation**, and fully roll-compensated lateral **oscillation** has been investigated at **frequencies** between 0.25 and 1.0 Hz when sitting on a rigid seat and when sitting on a compliant cushion, both without a backrest. Judgements of vibration discomfort and the transmission of lateral and roll **oscillation** through the seat cushion were obtained with 20 subjects. Relative to the rigid seat, the cushion increased lateral acceleration and roll **oscillation** at the lower **frequencies** and also increased discomfort during lateral **oscillation** (at **frequencies** less than 0.63 Hz), roll **oscillation** (at **frequencies** less than 0.4 Hz), and fully roll-compensated lateral **oscillation** (at **frequencies** between 0.315 and 0.5 Hz). The root-sums-of-squares of the **frequency**-weighted lateral and roll acceleration at the seat surface predicted the greater vibration discomfort when sitting on the cushion. The **frequency**-dependence of the predicted discomfort may be improved by adjusting the **frequency** weighting for roll acceleration at **frequencies** between 0.25 and 1.0 Hz.

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Contributors: Niko Bako, Adrijan Baric

Date: 2013-12-01

...**Oscillator**...Block scheme of the **oscillator**.
...Reference current and the oscillator frequency variations as a function of supply voltage and temperature obtained by simulations. (a) Reference current variation for typical (TT), slow (SS) and fast (FF) process corners with respect to the reference current at room temperature. (b) Frequency variation for typical, slow and fast corners with a supply voltage as a parameter with respect to frequency at room temperature.
...Miller compensated operational amplifier.
...Block scheme of the oscillator.
...Simulated open-loop AC characteristic of the amplifier.
...A low-power, temperature and supply voltage compensated current starved ring **oscillator**...Reference current and the **oscillator** **frequency** variations as a function of supply voltage and temperature obtained by simulations. (a) Reference current variation for typical (TT), slow (SS) and fast (FF) process corners with respect to the reference current at room temperature. (b) **Frequency** variation for typical, slow and fast corners with a supply voltage as a parameter with respect to **frequency** at room temperature.
...Si...A low-power, 3.82MHz **oscillator** based on a feedback loop is presented. The **oscillator** does not need a stable current reference to obtain a stable **frequency** independent of voltage and temperature variations because of the usage of negative feedback. The **frequency** variation, in the temperature range from −20°C to 80°C, is±0.6% and it depends only on the temperature coefficient of the resistor R, while the reference current variations are −11%/+25% in the same temperature range. The **oscillator** power consumption is 5.1μW and the active area is 0.09mm2. The proposed **oscillator** is implemented in a 0.18μm CMOS process and the simulation results are shown....The **oscillator** layout.
...Supply voltage compensated **frequency**...Simulated **oscillator** output.
...Temperature compensated **frequency** ... A low-power, 3.82MHz **oscillator** based on a feedback loop is presented. The **oscillator** does not need a stable current reference to obtain a stable **frequency** independent of voltage and temperature variations because of the usage of negative feedback. The **frequency** variation, in the temperature range from −20°C to 80°C, is±0.6% and it depends only on the temperature coefficient of the resistor R, while the reference current variations are −11%/+25% in the same temperature range. The **oscillator** power consumption is 5.1μW and the active area is 0.09mm2. The proposed **oscillator** is implemented in a 0.18μm CMOS process and the simulation results are shown.

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Contributors: Z.K. Peng, Z.Q. Lang, S.A. Billings, Y. Lu

Date: 2007-11-01

The output **frequency** response of a nonlinear system.
...The restoring force of a bilinear **oscillator**.
...Resonances of G4H(j2ωF)
...Analysis of bilinear **oscillators** under harmonic loading using nonlinear output **frequency** response functions...The percentage of the whole energy that the superharmonic components contain at different frequencies for different stiffness ratios.
...Bilinear **oscillator**...The restoring force of a bilinear oscillator.
...Nonlinear output **frequency** response function...Bilinear **oscillator** model.
...Bilinear oscillator model.
...The output **frequency** response of a linear system.
...The polynomial approximation result for a bilinear **oscillator**
...The polynomial approximation result for a bilinear oscillator
...In this paper, the new concept of nonlinear output **frequency** response functions (NOFRFs) is extended to the harmonic input case, an input-independent relationship is found between the NOFRFs and the generalized **frequency** response functions (GFRFs). This relationship can greatly simplify the application of the NOFRFs. Then, beginning with the demonstration that a bilinear **oscillator** can be approximated using a polynomial-type nonlinear **oscillator**, the NOFRFs are used to analyse the energy transfer phenomenon of bilinear **oscillators** in the **frequency** domain. The analysis provides insight into how new **frequency** generation can occur using bilinear **oscillators** and how the sub-resonances occur for the bilinear **oscillators**, and reveals that it is the resonant **frequencies** of the NOFRFs that dominate the occurrence of this well-known nonlinear behaviour. The results are of significance for the design and fault diagnosis of mechanical systems and structures which can be described by a bilinear **oscillator** model. ... In this paper, the new concept of nonlinear output **frequency** response functions (NOFRFs) is extended to the harmonic input case, an input-independent relationship is found between the NOFRFs and the generalized **frequency** response functions (GFRFs). This relationship can greatly simplify the application of the NOFRFs. Then, beginning with the demonstration that a bilinear **oscillator** can be approximated using a polynomial-type nonlinear **oscillator**, the NOFRFs are used to analyse the energy transfer phenomenon of bilinear **oscillators** in the **frequency** domain. The analysis provides insight into how new **frequency** generation can occur using bilinear **oscillators** and how the sub-resonances occur for the bilinear **oscillators**, and reveals that it is the resonant **frequencies** of the NOFRFs that dominate the occurrence of this well-known nonlinear behaviour. The results are of significance for the design and fault diagnosis of mechanical systems and structures which can be described by a bilinear **oscillator** model.

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Contributors: Yu.P. Emelianova, A.P. Kuznetsov, I.R. Sataev, L.V. Turukina

Date: 2013-02-01

Rotation numbers ν1–2 and ν2–3 versus the **frequency** detuning Δ1 for the system (11). Values of the parameters are λ1=1.3,λ2=1.9,λ3=1.8,Δ2=1.5 and μ=0.32.
...Schematic representation of a system of three coupled self-**oscillators**.
...The problem of growing complexity of the dynamics of the coupled phase **oscillators** as the number of **oscillators** in the chain increases is considered. The organization of the parameter space (parameter of the **frequency** detuning between the second and the first **oscillators** versus parameter of dissipative coupling) is discussed. The regions of complete synchronization, quasi-periodic regimes of different dimensions and chaos are identified. We discuss transformation of the domains of different dynamics as the number of **oscillators** grows. We use the method of charts of Lyapunov exponents and modification of the method of the chart of dynamical regimes to visualize two-**frequency** regimes of different type. Limits of applicability of the quasi-harmonic approximation and the features of the dynamics of the original system which are not described by the approximate phase equations are discussed for the case of three coupled **oscillators**....Subdivision of the chain of four oscillators by clusters for the three types of the phase locked pair of oscillators. Parameters are chosen in such a way that the system of oscillators is near the point of the saddle–node bifurcation.
...Trajectories on the phase torus. (a) resonant two-**frequency** regime with winding number w=1:2, (b) three-**frequency** regime.
...Trajectories on the phase torus. (a) resonant two-frequency regime with winding number w=1:2, (b) three-frequency regime.
...Synchronization and multi-**frequency** oscillations in the low-dimensional chain of the self-oscillators...(Color online). Chart of the Lyapunov’s exponents for the system of three coupled phase **oscillators** (5) for Δ2=1. The color palette is given and decrypted under the picture. The numbers indicate the tongues of the main resonant two-**frequency** regimes. These regimes are explained in the description of Fig. 5.
...(Color online). Chart of the Lyapunov’s exponents for the system of three coupled phase oscillators (5) for Δ2=1. The color palette is given and decrypted under the picture. The numbers indicate the tongues of the main resonant two-frequency regimes. These regimes are explained in the description of Fig. 5.
...Subdivision of the chain of four **oscillators** by clusters for the three types of the phase locked pair of **oscillators**. Parameters are chosen in such a way that the system of **oscillators** is near the point of the saddle–node bifurcation.
...(Color online). Charts of the Lyapunov’s exponents for the system of three coupled van der Pol oscillators (1). (a) λ=0.1,Δ2=0.05, (b) λ=0**.2,Δ2=0.15**. OD is a region of “oscillator death”. PBS is a region of partial broadband synchronization.
...Phase **oscillators**...Rotation numbers ν1–2 and ν2–3 versus the frequency detuning Δ1 for the system (11). Values of the parameters are λ1=1.3,λ2=1.9,λ3=1.8,Δ2=1.5 and μ=0.32.
... The problem of growing complexity of the dynamics of the coupled phase **oscillators** as the number of **oscillators** in the chain increases is considered. The organization of the parameter space (parameter of the **frequency** detuning between the second and the first **oscillators** versus parameter of dissipative coupling) is discussed. The regions of complete synchronization, quasi-periodic regimes of different dimensions and chaos are identified. We discuss transformation of the domains of different dynamics as the number of **oscillators** grows. We use the method of charts of Lyapunov exponents and modification of the method of the chart of dynamical regimes to visualize two-**frequency** regimes of different type. Limits of applicability of the quasi-harmonic approximation and the features of the dynamics of the original system which are not described by the approximate phase equations are discussed for the case of three coupled **oscillators**.

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Contributors: Feng Liu, JiaFu Wang, Wei Wang

Date: 1999-05-31

(a) The SNR vs noise intensity D for fs=30,15, and 100 Hz, respectively. (b) The mean synaptic input Isyn(t) vs time for fs=30 Hz and D=0.15 and 6, respectively. (c) The SNR for various **frequencies** for the cases of D=0.5 and 5, respectively, in the case of I0i=0.8 and I1=0.11, and Jij∈[−4,20]. (d) The SNR vs signal **frequency** for D=0.5 and 5, respectively, for the case of I0i∈[0,1] and I1=0.072.
...The **frequency** sensitivity...Intrinsic **oscillations**...The 40 Hz **oscillation**...(a) The SNR vs noise intensity D for fs=30,15, and 100 Hz, respectively. (b) The mean synaptic input Isyn(t) vs time for fs=30 Hz and D=0.15 and 6, respectively. (c) The SNR for various frequencies for the cases of D=0.5 and 5, respectively, in the case of I0i=0.8 and I1=0.11, and Jij∈[−4,20]. (d) The SNR vs signal **frequency** for D=0.5 and 5, respectively, for the case of I0i∈[0,1] and I1=0.072.
...The phenomena of **frequency** sensitivity in weak signal detection and the 40 Hz oscillation in a neuronal network have been interpreted based on the intrinsic oscillations of the system. There exists a most sensitive **frequency** range of 20–60 Hz, over which the signal-to-noise ratio has a large value. This results from the resonance between the subthreshold intrinsic oscillation and the periodic signal. The network can exhibit the synchronous 40 Hz oscillation only with constant bias, which is due to the intrinsic features of neurons and long-range interactions between them....The **frequency** fi and the corresponding height H of the main peak in PSD of Isyn(t) vs (a) A for the case of I0i∈[0,3.5]; (b) M in the case of Jij∈[−5,10].
...**Frequency** characteristics and intrinsic oscillations in a neuronal network...The phenomena of **frequency** sensitivity in weak signal detection and the 40 Hz **oscillation** in a neuronal network have been interpreted based on the intrinsic **oscillations** of the system. There exists a most sensitive **frequency** range of 20–60 Hz, over which the signal-to-noise ratio has a large value. This results from the resonance between the subthreshold intrinsic **oscillation** and the periodic signal. The network can exhibit the synchronous 40 Hz **oscillation** only with constant bias, which is due to the intrinsic features of neurons and long-range interactions between them....I0i∈[0,2] and Jij∈[−1,10]. (a) The spatiotemporal firing pattern is plotted by recording the firing time tni defined by Xi(tni)>0 and Xi(tni−)**frequency** fi and the corresponding height H of the main peak in PSD of Isyn(t) for different coupling strength.
... The phenomena of **frequency** sensitivity in weak signal detection and the 40 Hz **oscillation** in a neuronal network have been interpreted based on the intrinsic **oscillations** of the system. There exists a most sensitive **frequency** range of 20–60 Hz, over which the signal-to-noise ratio has a large value. This results from the resonance between the subthreshold intrinsic **oscillation** and the periodic signal. The network can exhibit the synchronous 40 Hz **oscillation** only with constant bias, which is due to the intrinsic features of neurons and long-range interactions between them.

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Contributors: Weixiong Chen, Quanbin Zhao, Yingchun Wang, Palash Kumar Sen, Daotong Chong, Junjie Yan

Date: 2016-09-01

Schematic diagram of steam jet [1–4].
...Submerged steam jet condensation is widely applied in various fields because of its high heat transfer efficiency. Condensation **oscillation** is a major character of submerged steam turbulent jet, and it significantly affects the design and safe operation of industrial equipment. This study is designed to reveal the mechanism of the low-**frequency** pressure **oscillation** of steam turbulent jet condensation and determine its affected region. First, pressure **oscillation** signals with low **frequency** are discovered in the downstream flow field through **oscillation** **frequency** spectrogram and power analysis. The **oscillation** **frequency** is even lower than the first dominant **frequency**. Moreover, the critical positions, where the low-**frequency** pressure **oscillation** signals appear, move downstream gradually with radial distance and water temperature. However, these signals are little affected by the steam mass flux. Then, the regions with low-**frequency** pressure **oscillation** occurring are identified experimentally. The affected width of the low-**frequency** pressure **oscillation** is similar to the turbulent jet width. Turbulent jet theory and the experiment results collectively indicate that the low-**frequency** pressure **oscillation** is generated by turbulent jet vortexes in the jet wake region. Finally, the angular coefficients of the low-**frequency** affected width are obtained under different water temperatures. Angular coefficients, ranging from 0.2268 to 0.2887, decrease with water temperature under test conditions....**Frequency** spectrograms distribution along the axial direction (R/D=2).
...**Frequency** spectrograms under radial position of R/D=3.0 and R/D=4.0.
...Half affected width of pressure **oscillation**.
...Submerged steam jet condensation is widely applied in various fields because of its high heat transfer efficiency. Condensation oscillation is a major character of submerged steam turbulent jet, and it significantly affects the design and safe operation of industrial equipment. This study is designed to reveal the mechanism of the low-**frequency** pressure oscillation of steam turbulent jet condensation and determine its affected region. First, pressure oscillation signals with low **frequency** are discovered in the downstream flow field through oscillation **frequency** spectrogram and power analysis. The oscillation **frequency** is even lower than the first dominant **frequency**. Moreover, the critical positions, where the low-**frequency** pressure oscillation signals appear, move downstream gradually with radial distance and water temperature. However, these signals are little affected by the steam mass flux. Then, the regions with low-**frequency** pressure oscillation occurring are identified experimentally. The affected width of the low-**frequency** pressure oscillation is similar to the turbulent jet width. Turbulent jet theory and the experiment results collectively indicate that the low-**frequency** pressure oscillation is generated by turbulent jet vortexes in the jet wake region. Finally, the angular coefficients of the low-**frequency** affected width are obtained under different water temperatures. Angular coefficients, ranging from 0.2268 to 0.2887, decrease with water temperature under test conditions....Frequency spectrograms under radial position of R/D=3.0 and R/D=4.0.
...Schematic diagram of experimental system [21].
...**Frequency** spectrograms of condensation **oscillation** [21].
...Oscillation power axial distribution for low frequency region.
...Half affected width of pressure oscillation.
...Pressure **oscillation**...**Oscillation** power axial distribution for low **frequency** region.
... Submerged steam jet condensation is widely applied in various fields because of its high heat transfer efficiency. Condensation **oscillation** is a major character of submerged steam turbulent jet, and it significantly affects the design and safe operation of industrial equipment. This study is designed to reveal the mechanism of the low-**frequency** pressure **oscillation** of steam turbulent jet condensation and determine its affected region. First, pressure **oscillation** signals with low **frequency** are discovered in the downstream flow field through **oscillation** **frequency** spectrogram and power analysis. The **oscillation** **frequency** is even lower than the first dominant **frequency**. Moreover, the critical positions, where the low-**frequency** pressure **oscillation** signals appear, move downstream gradually with radial distance and water temperature. However, these signals are little affected by the steam mass flux. Then, the regions with low-**frequency** pressure **oscillation** occurring are identified experimentally. The affected width of the low-**frequency** pressure **oscillation** is similar to the turbulent jet width. Turbulent jet theory and the experiment results collectively indicate that the low-**frequency** pressure **oscillation** is generated by turbulent jet vortexes in the jet wake region. Finally, the angular coefficients of the low-**frequency** affected width are obtained under different water temperatures. Angular coefficients, ranging from 0.2268 to 0.2887, decrease with water temperature under test conditions.

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Contributors: Olivier Audouin, Jacques Bodin

Date: 2007-02-20

Extensive slug-test experiments have been performed at the Hydrogeological Experimental Site (HES) of Poitiers in France, made up of moderately fractured limestones. All data are publicly available through the “H+” database, developed within the scope of the ERO program (French Environmental Research Observatory, http://hplus.ore.fr). Slug-test responses with high-**frequency** (>0.12Hz) oscillations have been consistently observed in wells equipped with multiple concentric casing. These oscillations are interpreted as the result of inertia-induced fluctuations of the water level in the annular space between the inner and outer casing. In certain cases, these high-**frequency** oscillations overlap with lower **frequency** (**frequency** domain, in order to remove the high-**frequency** component by a signal-filtering method. The corrected signals have been interpreted with the model of [McElwee, C.D., Zenner, M., 1998. A nonlinear model for analysis of slug-test data. Water Resour. Res. 34 (1), 55–66.], which accounts for the inertia of the water-column above the well screen, non-linear head losses in the well, and neglects the aquifer storage (quasi-steady-state approximation). Hydraulic conductivity values interpreted from dual-**frequency** slug-tests compare well to those interpreted from “standard” overdamped or underdamped slug-test responses....Filter shape in the frequency domain for ρ=0.9.
...**Frequency** spectrum of the slug-test response in HES well M05, for an initial head displacement H0=0.2m (slug-test reference=STM5_02).
...Filtering of high-**frequency** **oscillations**: example of processing of the slug test STM5_02 (HES well M05, initial head displacement H0=0.2m).
...Curve fitting of HES slug-test responses with the model of McElwee and Zenner (1998).
...High-**frequency** **oscillations**...Opinion - Analysis of slug-tests with high-**frequency** oscillations...Filter shape in the **frequency** domain for ρ=0.9.
...Extensive slug-test experiments have been performed at the Hydrogeological Experimental Site (HES) of Poitiers in France, made up of moderately fractured limestones. All data are publicly available through the “H+” database, developed within the scope of the ERO program (French Environmental Research Observatory, http://hplus.ore.fr). Slug-test responses with high-**frequency** (>0.12Hz) **oscillations** have been consistently observed in wells equipped with multiple concentric casing. These **oscillations** are interpreted as the result of inertia-induced fluctuations of the water level in the annular space between the inner and outer casing. In certain cases, these high-**frequency** **oscillations** overlap with lower **frequency** (**oscillations**, which leads to complex responses that cannot be interpreted using conventional models. Slug-test data have been processed in the Fourier-**frequency** domain, in order to remove the high-**frequency** component by a signal-filtering method. The corrected signals have been interpreted with the model of [McElwee, C.D., Zenner, M., 1998. A nonlinear model for analysis of slug-test data. Water Resour. Res. 34 (1), 55–66.], which accounts for the inertia of the water-column above the well screen, non-linear head losses in the well, and neglects the aquifer storage (quasi-steady-state approximation). Hydraulic conductivity values interpreted from dual-**frequency** slug-tests compare well to those interpreted from “standard” overdamped or underdamped slug-test responses....Interpretation of high-frequency oscillations: inertia-induced water level fluctuations in the annular space between the inner PVC casing and the outer steel casing.
...Freq...Interpretation of high-**frequency** **oscillations**: inertia-induced water level fluctuations in the annular space between the inner PVC casing and the outer steel casing.
...High-**frequency** oscillations...Typical slug-test responses in HES wells. (a) “Standard” overdamped response; (b) “standard” underdamped response with low-**frequency** **oscillations**; (c) overdamped response with high-**frequency** **oscillations**; (d) underdamped response with dual-**frequency** **oscillations**.
...Typical slug-test responses in HES wells. (a) “Standard” overdamped** response**; (b) “standard” underdamped **response **with low-frequency oscillations; (c) overdamped **response **with high-frequency oscillations; (d) underdamped **response **with dual-frequency oscillations.
...Filtering of high-frequency oscillations: example of processing of the slug test STM5_02 (HES well M05, initial head displacement H0=0.2m).
... Extensive slug-test experiments have been performed at the Hydrogeological Experimental Site (HES) of Poitiers in France, made up of moderately fractured limestones. All data are publicly available through the “H+” database, developed within the scope of the ERO program (French Environmental Research Observatory, http://hplus.ore.fr). Slug-test responses with high-**frequency** (>0.12Hz) **oscillations** have been consistently observed in wells equipped with multiple concentric casing. These **oscillations** are interpreted as the result of inertia-induced fluctuations of the water level in the annular space between the inner and outer casing. In certain cases, these high-**frequency** **oscillations** overlap with lower **frequency** (<0.05Hz) **oscillations**, which leads to complex responses that cannot be interpreted using conventional models. Slug-test data have been processed in the Fourier-**frequency** domain, in order to remove the high-**frequency** component by a signal-filtering method. The corrected signals have been interpreted with the model of [McElwee, C.D., Zenner, M., 1998. A nonlinear model for analysis of slug-test data. Water Resour. Res. 34 (1), 55–66.], which accounts for the inertia of the water-column above the well screen, non-linear head losses in the well, and neglects the aquifer storage (quasi-steady-state approximation). Hydraulic conductivity values interpreted from dual-**frequency** slug-tests compare well to those interpreted from “standard” overdamped or underdamped slug-test responses.

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