A novel strategy of probability density function （PDF） shape control is proposed in stochastic systems. The control er is designed whose parameters are optimal y obtained through the improved particle swarm optimiza...
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A novel strategy of probability density function （PDF） shape control is proposed in stochastic systems. The control er is designed whose parameters are optimal y obtained through the improved particle swarm optimization algorithm. The parameters of the control er are viewed as the space position of a particle in particle swarm optimization algorithm and updated continual y until the control er makes the PDF of the state variable as close as possible to the expected PDF. The proposed PDF shape control technique is compared with the equivalent linearization technique through simulation experiments. The results show the superiority and the effectiveness of the proposed method. The control er is excellent in making the state PDF fol ow the expected PDF and has the very smal error between the state PDF and the expected PDF, solving the control problem of the PDF shape in stochastic systems effectively.
The ultraviolet continuum generation in the fundamental mode of photonic crystal fibers designed and fabricated in our lab are experimentally *** the pump works in the normal dispersion regions of 780 nm and 830 nm,an...
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The ultraviolet continuum generation in the fundamental mode of photonic crystal fibers designed and fabricated in our lab are experimentally *** the pump works in the normal dispersion regions of 780 nm and 830 nm,and the average powers increase from 100 to 500 m W,anti-Stokes signals can be efficiently generated based on the phase-matched degenerate four-wave *** cross-phase modulation between the pump and the generated anti-Stokes signals can effectively extend the continuum into the ultraviolet wavelength *** can provide an efficient light source for ultraviolet photonics and spectroscopy.
Laser displacement sensors enable contactless depth measurements, which can be used in criminal investigations for non-destructive trace measurements of cartridge cases. Due to the high curvature and reflectivity of t...
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This paper is devoted to the event-triggered H∞ static output feedback control of linear discrete-time networked control systems. With the help of zero-holder, a time-delay formulation is adopted to describe the even...
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Aleatoric uncertainty inherent in degradation data and epistemic uncertainty introduced by a research method directly affect the trustworthiness of health prognosis, specifically in terms of the state of health (SOH) ...
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Geometric distortions are simple and effective at- tacks rendering many watermarking methods useless. They make detection and extraction of the embedded watermark difficult or even impossible by destroying the synchro...
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Geometric distortions are simple and effective at- tacks rendering many watermarking methods useless. They make detection and extraction of the embedded watermark difficult or even impossible by destroying the synchroniza- tion between the watermark reader and the embedded water- mark. In this paper, we propose a blind content-based image watermarking scheme against geometric distortions. Firstly, the MSER detector is adopted to extract a set of maximally stable extremal regions which are affine covariant and robust to geometric distortions and common signal processing. Sec- ondly, every original MSER is fitted into an elliptical region that was proved to be affine invariant. In order to achieve rota- tion invariance, an image normalization process is performed to transform the elliptical regions into circular ones. Finally, watermarks are repeatedly embedded into every circular disk by modifying the wavelet transform coefficients. Experimen- tal results on standard benchmark demonstrate that the pro- posed scheme is robust to geometric distortions as well as common signal processing.
In the field repair application of laser metal deposition(LMD),the kinds of powder materials that can be used are limited,while the equipment components are made of various *** many components have to be repaired with...
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In the field repair application of laser metal deposition(LMD),the kinds of powder materials that can be used are limited,while the equipment components are made of various *** many components have to be repaired with heterogeneous ***,it is difficult to match the mechanical properties between the repaired layer and the substrate due to the diff erent *** on the high flexibility of raw materials and processes in LMD,an in-situ alloying method is proposed herein for tailoring the mechanical properties of LMDed *** diff erent mixing ratios of Fe314 and 316 L stainless steel powders as the control parameter,the microstructure and mechanical properties of B-bearing austenitic stainless steel fabricated by LMD in-situ alloying with diff erent proportions of Fe314 and 316 L particles were *** the increase in the concentration of 316 L steel,the volume fraction of the eutectic phase in deposited B-bearing austenitic stainless steel reduced,the size of the austenite dendrite increased,the yield strength and ultimate tensile strength decreased monotonically,while the elongation increased ***,the fracture mode changed from quasi-cleavage fracture to ductile *** adding 316 L powder,the yield strength,tensile strength,and elongation of deposited B-bearing austenitic stainless steel could be adjusted within the range of 712 MPa–257 MPa,1325 MPa–509 MPa,and 8.7%–59.3%,***,this work provides a new method and idea for solving the performance matching problem of equipment components in the field repair.
In order to achieve ultra-low emissions of SO_(2)and NO_(x),the oxygen blast furnace with sintering flue gas injection is presented as a promising novel *** CO_(2)emission was examined,and a cost analysis of the proce...
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In order to achieve ultra-low emissions of SO_(2)and NO_(x),the oxygen blast furnace with sintering flue gas injection is presented as a promising novel *** CO_(2)emission was examined,and a cost analysis of the process was *** results show that in the cases when the top gas is not circulated(Cases 1–3),and the volume of injected sintering flue gas per ton of hot metal is below about 1250 m^(3),the total CO_(2)emissions decrease first and then increase as the oxygen content of the blast *** the volume of injected sintering flue gas per ton of hot metal exceeds approximately 1250 m^(3),the total CO_(2)emissions gradually *** the recirculating top gas and the vacuum pressure swing adsorption are considered,the benefits of recovered gas can make the ironmaking cost close to or even lower than that of the ordinary blast ***,the implementation of this approach leads to a substantial reduction in total CO_(2)emissions,with reductions of 69.13%(Case 4),70.60%(Case 5),and 71.07%(Case 6),*** integrating previous research and current findings,the reasonable oxygen blast furnace with sintering flue gas injection can not only realize desulfurization and denitrification,but also achieve the goal of reducing CO_(2)emissions and ironmaking cost.
Remote sensing image recognition has been widely used in civil and military fields. In view of plenty of interference factors in remote-sensing aircraft such as shade, noise, the changing of perspective, etc. An impro...
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The semiconductor-based photoanodes have shown great potential on photoelectrochemical(PEC)hydrogen *** to the pristine semiconductor,photoanodes fabricated with doped semiconductors exhibit modulated bandgap structur...
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The semiconductor-based photoanodes have shown great potential on photoelectrochemical(PEC)hydrogen *** to the pristine semiconductor,photoanodes fabricated with doped semiconductors exhibit modulated bandgap structure and enhanced charge separation efficiency,demonstrating improved optoelectronic *** this work,we develop a colloidal cation exchange(CE)strategy on versatile synthesis of heterovalent doped chalcogenide semiconductor thin films with high surface *** Ag-doped CdSe(CdSe:Ag)thin films as an example,the organized centimeter-scale CdSe:Ag films with nanometer-scale thickness(thickness around 80 nm,length×width around 1.5 cm×1.2 cm)exhibit enhanced optical absorbance ability and charge carrier density by tuning the energy levels of conduction and valence bands as well as improved electrical conductivity by Ag dopants compared to the pristine CdSe film obtained by the vapor-phase vacuum deposition *** the meantime,the surface roughness of the as-prepared semiconductor thin films is also increased with abundantly exposed active sites to facilitate accessibility to water for hydrogen generation and suppress photogenerated carrier *** CdSe:Ag film photoanodes exhibit superb PEC hydrogen generation performance with a photocurrent density of 0.56 mA/cm^(2) at 1.23 V versus reversible hydrogen electrode,which is nearly 3 times higher than the pristine CdSe *** work provides a new strategy on colloidal synthesis of photoelectrodes with modulated heterovalent doping and surface roughness for PEC applications.
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