Autonomous Boolean networks(ABNs)have been successfully applied to the generation of random number due to their complex nonlinear dynamics and convenient on-chip *** of the ABNs used for random number generators show ...
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Autonomous Boolean networks(ABNs)have been successfully applied to the generation of random number due to their complex nonlinear dynamics and convenient on-chip *** of the ABNs used for random number generators show a symmetric topology,despite their oscillations dependent on the inconsistency of time delays along *** address this issue,we suggest an asymmetrical autonomous Boolean network(aABN)and show numerically that it provides large amplitude oscillations by using equal time delays along links and the same logical *** results show that the chaotic features of aABN are comparable to those of symmetric ABNs despite their being made of fewer ***,we put forward a random number generator based on aABN and show that it generates the random numbers passing the NIST test suite at 100 Mbits/*** unpredictability of the random numbers is analyzed by restarting the random number generator *** aABN may replace symmetrical ABNs in many applications using fewer nodes and,in turn,reducing power consumption.
A series of Ca10Na(PO4)7:Ce3+/Tb3+/Mn2+(CNPO:Ce3+/Tb3+/Mn2+) phosphors with high brightness were synthesized by high-temperature solid-state method. X-ray diffraction(XRD), scanning electron microscopy(SEM), diffuse r...
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A series of Ca10Na(PO4)7:Ce3+/Tb3+/Mn2+(CNPO:Ce3+/Tb3+/Mn2+) phosphors with high brightness were synthesized by high-temperature solid-state method. X-ray diffraction(XRD), scanning electron microscopy(SEM), diffuse reflectance spectra(DRS), photo luminescence(PL) spectra, luminescence decay curves and thermally stability were performed to characterize the as-prepared samples. For Ce3+-doped samples, an intense and broad band emission is present under 265 nm excitation. When Ce3+and Tb3+are codoped, energy transfer(ET) process from Ce3+ to Tb3+ is demonstrated with electric dipole-dipole interaction. The internal and external quantum efficiencies(QEs) of CNPO:0.15 Ce3+, 0.04 Tb3+, 0.005 Mn2+are measured to 76.79% and 54.11% under 265 nm excitation and temperature-dependent PL intensity can remain 51.78% at 150 ℃ of its initial intensity at 25 ℃. It is indicated that single-phased white lightemitting CNPO:Ce3+/Tb3+/Mn2+phosphor can serve as a promising phosphor for illumination devices.
In this paper, the performance of wavelet transform on the detection and location of pipeline leak are explored. The effects of three wavelets on different thresholds and different decomposition layers are studied. Fi...
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By inserting an air cavity into a one-dimensional photonic crystal of LiF/GaSb, a tunable filter covering the whole visible range is proposed. Following consideration of the dispersion of the materials, through modula...
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By inserting an air cavity into a one-dimensional photonic crystal of LiF/GaSb, a tunable filter covering the whole visible range is proposed. Following consideration of the dispersion of the materials, through modulating the thickness of the air cavity, we demonstrate that a single resonant peak can shift from 416.1 to 667.3 nm in the band gap at normal incidence by means of the transfer matrix method. The research also shows that the transmittance of the channel can be maximized when the number of periodic Li F/Ga Sb layers on one side of the air defect layer is equal to that of the other side. When adding a period to both sides respectively, the full width at half maximum of the defect mode is reduced by one order of magnitude. This structure will provide a promising approach to fabricate practical tunable filters in the visible region with ultra-wide tuning range.
We systematically investigate the four-wave mixing(FWM)spectrum in a dual-cavity hybrid optomechanical system,which is made up of one optical cavity with an ensemble of two-level atoms and another with a mechanical **...
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We systematically investigate the four-wave mixing(FWM)spectrum in a dual-cavity hybrid optomechanical system,which is made up of one optical cavity with an ensemble of two-level atoms and another with a mechanical *** this work,we propose that the hybrid dual-cavity optomechanical system can be employed as a highly sensitive mass sensor due to the fact that the FWM spectrum generated in this system has a narrow spectral width and the intensity of the FWM can be easily tuned by controlling the coupling strength(cavity-cavity,atom-cavity).More fascinatingly,the dual-cavity hybrid optomechanical system can also be used as an all-optical switch in view of the easy on/off control of FWM signals by adjusting the atom-pump detuning to be positive or *** proposed schemes have great potential applications in quantum information processing and highly sensitive detection.
The sensitivity to fault reflection is very important for larger dynamic range in fiber fault detection *** time delay signature(TDS)of chaotic laser formed by optical feedback can solve the sensitivity limitation of ...
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The sensitivity to fault reflection is very important for larger dynamic range in fiber fault detection *** time delay signature(TDS)of chaotic laser formed by optical feedback can solve the sensitivity limitation of photodetector in fiber fault *** TDS corresponds to the feedback position and the fault reflection can be detected by the laser *** sensitivity to feedback level of circular-side hexagonal resonator(CSHR)microcavity laser is numerically simulated and the feedback level boundaries of each output dynamic state are *** peak level of TDS is utilized to analyze the *** demonstration is presented in two aspects:the minimum feedback level when the TDS emerges and the variation degree of TDS level on feedback level *** results show that the CSHR microcavity laser can respond to the feedback level of 0.07%,corresponding to-63-dB feedback *** to conventional distributed feedback laser,the sensitivity improves almost 20 dB due to the shorter internal cavity length of CSHR microcavity ***,1%feedback level changing will induce 1.001 variation on TDS level,and this variation degree can be influenced by other critical internal parameters(active region side length,damping rate,and linewidth enhancement factor).
Stable porphyrin-oxygenated carbon nanomaterial dispersions were prepared by blending porphyrin solutions with hydroxyl groups modified multi-walled carbon nanotubes(MWNTs-OH)and graphene oxide(GO)dispersions,*** nonl...
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Stable porphyrin-oxygenated carbon nanomaterial dispersions were prepared by blending porphyrin solutions with hydroxyl groups modified multi-walled carbon nanotubes(MWNTs-OH)and graphene oxide(GO)dispersions,*** nonlinearity and optical limiting(OL)property of these blends are investigated in nanosecond *** show that the OL performance of the blends can be tuned by changing the concentrations ratio of porphyrin and oxygenated carbon *** high concentration of oxygenated carbon nanomaterial leads to the poor OL ***,with the moderate concentration,the blends exhibit the low threshold value of OL and the enhanced OL performance at high fluence *** superior OL performance can be attributed to complementary mechanisms and possible photoinduced electron or energy transfer between porphyrin moiety and oxygenated carbon nanomaterials.
When the loader boom is lifted and lowered, the hydraulic pump operates at high peak power levels. In this process, the hydraulic valve port dissipates the gravitational potential energy of the boom. Consequently, the...
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An optical funnel,which performs as a passive electromagnetic compressor,can guide electromagnetic waves from a wide inlet to a narrow outlet without reflectance/scattering and squeeze electromagnetic fields uniformly...
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An optical funnel,which performs as a passive electromagnetic compressor,can guide electromagnetic waves from a wide inlet to a narrow outlet without reflectance/scattering and squeeze electromagnetic fields uniformly to an air *** this study,an optical funnel is designed by precisely filling subwavelength ceramic blocks with a gradient refractive index inside a tapered *** gradient refractive index is designed by transformation optics,which is isotropic and all above unit,thus exhibiting a broadband *** to the mechanism of impedance matching over the whole funnel,extremely low reflectance/scattering and stable enhancement of fields can be *** field enhancement factor in different regions of the funnel(e.g.,in the air neck)can be flexibly designed just by modifying the funnel-width ratios.
Aiming at the non-contact detection scene of GPR,it is necessary to adjust the repetition frequency of transmitting pulse waveform flexibly,and a GPR pulse signal design based on FPGA is *** scheme uses FPGA to contro...
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ISBN:
(数字)9789887581536
ISBN:
(纸本)9781665482561
Aiming at the non-contact detection scene of GPR,it is necessary to adjust the repetition frequency of transmitting pulse waveform flexibly,and a GPR pulse signal design based on FPGA is *** scheme uses FPGA to control the generation of adjustable pulse signals,which are amplified by high-frequency power amplifier circuit,and the signal repetition frequency can be adjusted by *** theory of transmitting pulse waveform design is analyzed,the FPGA logic circuit is designed to generate pulse signal,and the high frequency power amplifier circuit is designed to solve the problem of low power of FPGA *** effectiveness of the scheme is verified by *** results show that the pulse signal generated by the scheme has stable frequency amplitude and the output power meets the requirements of non-contact *** with the traditional pulse signal generation device using switching devices,the structure is simple and the pulse signal can be set flexibly.
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