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We present experimental observations of soliton pulsations in the net normal-dispersion fiber laser by using the dispersive Fourier transform (DFT) technique. According to the pulsating characteristics, the soliton pulsations are classified as visible and invisible soliton pulsations. The visible soliton pulsation is converted from single- into dual-soliton pulsation with the common characteristics of energy oscillation and bandwidth breathing. The invisible soliton pulsation undergoes periodic variation in the spectral profile and peak power but remains invariable in pulse energy. The reason for invisible soliton pulsation behavior is periodic oscillation of the pulse inside the soliton molecule. These results could be helpful in deepening our understanding of the soliton pulsation phenomena.

We have developed and analysed logic NOR, NAND and XNOR gates based on two dimensional (2D) photonic crystals at a wavelength of 1.55 μm. The interference and self-collimation effects are used to design logic gates, which control the output by adjusting the phase difference to achieve constructive or destructive interference. The splitter is a line defect of the photonic crystal with a row of periodically arranged air rods. The radius of the defect rods depends on the function of the logic element. The use of these logic gates can reduce the size of logic devices.

Combining high-speed schlieren technology and infrared imaging technology, related research has been carried out on the influence of parameters such as actuation voltage, repetition frequency, and electrode size of an actuator on the discharge characteristics, induced flow field characteristics, and thermal characteristics of nanosecond pulsed dielectric barrier discharge. The results show that increasing the value of the actuation voltage can significantly increase the actuation intensity, and the plasma discharge area is significantly extended. Increasing the repetition frequency can increase the number of discharges per unit time. Both will cause more energy input and induce more changes in the flow field. The effect of temperature rise is more significant. The width of the covered electrode will affect the potential distribution during the discharge process, which in turn will affect the extension process of the plasma discharge filament. Under the same actuation intensity, the wider the covered electrode, the larger range the induced flow field and temperature rise is. Preliminary experimental analyses of high-frequency actuation characteristics, temperature field characteristics, flow field characteristics and actuation parameter settings provide support for the parameter selection and partial mechanism analysis of plasma anti-icing.

We study the cosmological propagation of gravitational waves (GWs) beyond general relativity (GR) across homogeneous and isotropic backgrounds. We consider scenarios in which GWs interact with an additional tensor field and use a parametrized phenomenological approach that generically describes their coupled equations of motion. We analyze four distinct classes of derivative and non-derivative interactions: mass, friction, velocity, and chiral. We apply the WKB formalism to account for the cosmological evolution and obtain analytical solutions to these equations. We corroborate these results by analyzing numerically the propagation of a toy GW signal. We then proceed to use the analytical results to study the modified propagation of realistic GWs from merging compact binaries, assuming that the GW signal emitted is the same as in GR. We generically find that tensor interactions lead to copies of the originally emitted GW signal, each one with its own possibly modified dispersion relation. These copies can travel coherently and interfere with each other leading to a scrambled GW signal, or propagate decoherently and lead to echoes arriving at different times at the observer that could be misidentified as independent GW events. Depending on the type of tensor interaction, the detected GW signal may exhibit amplitude and phase distortions with respect to a GW waveform in GR, as well as birefringence effects. We discuss observational probes of these tensor interactions with both individual GW events, as well as population studies for both ground- and space-based detectors., Updated to journal version

Current demand side resources gradually become an important part of promoting renewable energy given, using price, taxes, subsidies and other economic mechanism, encourage users to change electricity behavior, complete with the maximization of expected load curve fitting, to achieve the peak cut, or peak adjustment, to maximize the utilization of renewable energy power generation. Based on the reasonable classification and definition of user types and demand-side resources, this paper constructs a grid load influence degree model of compatible demand-side resources, and quantitatively studies the contribution degree of demand-side response to promoting renewable energy consumption.

The first generation of multifunctional home fitness recliners is a kind of home-use portable fitness equipment that coexists with multiple functions and can be easily adjusted for strength. The fitness equipment adopts the bionic “fish-shaped” design, and uses the principle of morphological bionics to achieve the simplicity required by design and meet today’s aesthetics. While improving the aesthetics of the design equipment, it also meets the requirements of ergonomics, thereby improving the user’s sports experience. The device uses polyformaldehyde plastic, ABS plastic, shell ABS plastic (natural plastic in the groove), polyamide fiber, PVC artificial leather, plywood, sponge, rubber sponge and other plastic materials that meet national standards. 35 # steel, cold rolled steel rectangular tube, spring steel, tungsten steel and other materials that meet various technical indicators. Under the premise of safe use of equipment, multiple exercise uses can be realized.

Introducing disorder into a periodic nanostructure can lead to specific optical behaviors. We present a method of anodic oxidation by adjusting the applied voltage and process time to introduce disorder to TiO2 nanotubes. The surface morphology of TiO2 was numerically investigated according to the morphologies measured with a scanning electron microscope by imaging processing and a statistical method. TiO2 nanotubes obtained under different fabrication conditions have various tube radii ranging from 20-40 nm and wall thicknesses ranging from 20-70 nm. We also evaluated the degree of disorder of the tube radius of the TiO2 nanotubes. The reflected scattering light distributions of laser sources were optically measured at different observing distances, which indicate that the presence of nanotubes enhances the scattering effect, reducing the scattered light intensity by more than 75%, and provide the relationship between the scattering effect and surface morphology of nanotubes. This discovery offers TiO2 nanotubes important application prospects in optical limiting and light confinement, such as stealth coating.