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Simulating Defensive Trajectories inside American Soccer regarding Forecasting League Average Shielding Moves.
We develop a watt-level 725 nm continuous-wave tunable narrow linewidth injection-locked Tisapphire laser. The seed laser is frequency-locked on a Fabry-Perot cavity to narrow the linewidth and stabilize the frequency. Because the wavelength of the seed laser is located at the edge of the gain profile of the Tisapphire crystal, it is difficult to injection-lock the Tisapphire laser at 725 nm. A cavity mirror, which has a long-pass-filter coating with a sharp edge, is used in the Tisapphire cavity to suppress mode competition from the long wavelength side. This method effectively reduces the power requirement of the seed laser at 725 nm, and the Tisapphire laser can be injection-locked at higher output power. As a result, a 1 W output power with a 27% slope efficiency is achieved in the injection-locked laser, and a 210 mW UV laser is obtained in a subsequent second-harmonic generation stage. To the best of our knowledge, this is the shortest wavelength for the watt-level injection-locked continuous-wave Tisapphire laser. This laser will be used in a mercury optical lattice clock in the future.In this study, a high-sensitivity intensity-interrogated fiber sensor integrated with ferrofluids is proposed for the measurement of a weak magnetic field (MF) with resolved temperature cross-sensitivity. The MF sensor is fabricated simply by an offset tapering single-mode fiber concatenated with a multimode fiber (MMF), which is then encapsulated into a capillary tube filled with ferrofluids. In the presence of MMF, stronger mode coupling could be achieved over the S-tapered fiber region. Its spectral response to variations in the applied MF intensity and ambient temperature have been investigated in detail. The proposed sensor shows a high MF sensitivity up to -0.1130dB/Oe for the measurement range of 40 to 120 Oe, which, to our best knowledge, is higher than other previously reported MF sensors. And moreover, the measurement errors caused by temperature cross-sensitivity have been corrected by using a sensing matrix for the temperature range of 25°C to 35°C. Our proposed MF sensor possesses the advantages of high sensitivity, low cost, and applicability for applications in weak MF measurements.The self-mixing interference (SMI) signal carries the information of the external moving object, which has great physical significance and application prospects for extracting and analyzing the information of the external object. In this paper, we propose a vibration measurement method based on a reverse point recognition algorithm on the SMI laser signal. By extracting and analyzing the hill and valley values of the SMI signal to determine the reverse point, combined with the semifringe counting method, the vibration information of external objects can be accurately extracted. The method we propose simplifies the displacement reconstruction process with high accuracy. The simulation and experimental results show that this method can achieve high-precision measurements of microvibration with an absolute error of less than 19 nm.This paper proposes the automatic lens-splitting optimization algorithm to correct spherical aberration by the interaction between ZEMAX and MATLAB. This method tackled the problem that classic optimization cannot add the elements automatically. A high numerical aperture collimator is considered for the test sample, and the selection of four thickness constraints (minimum center and edge of glass and air thickness constraints) is discussed. To determine the feasibility and applicability of this method, more design systems (a retro-focus objective system and a telesystem) are tested. The simulated results under the feasible thickness constraints show that the automatic lens-splitting optimization algorithm generates reasonable and realizable solutions.A denoising method based on singular value decomposition (SVD) and variational mode decomposition (VMD) is proposed for wind lidar. Utilizing the covariance matrix based lidar signal simulation model, the performance of VMD, SVD, and VMD-SVD is evaluated. The results show that the VMD-SVD method is of better performance, and the output signal-to-noise ratio (SNR) is about 12 dB at the input SNR of -9dB. The actual lidar signals processing is performed with this combined denoising method, and the detection range and wind speed at pulse accumulation numbers of 50,100, and 300 are compared. We set the wind speed resulting from noisy signal with pulse accumulation number of 300 as the reference wind speed, and the mean value and standard deviation of wind differences are analyzed. The results show that the denoising method can not only increase the detection range while ensuring the accuracy of wind speed estimation but also achieve the same detection distance with fewer pulse accumulations, thereby improving the temporal resolution. For the pulse accumulation number of 50, the detection range is extended to 24 km from 18.45 km, and the standard deviation of speed difference is 0.88 m/s; for the same detection range, the temporal resolution is increased by about 6 times.A novel, to the best of our knowledge, optical arrangement is evaluated for performing single-shot femtosecond laser electronic excitation tagging in a 16-point grid (Grid-FLEET) with single-ended optical access. The optical arrangement includes a diffractive optical element beam splitter to produce a grid of laser beams in a simplified, flexible, and efficient manner for tracer-free multi-component molecular tagging velocimetry in a two-dimensional field. Analysis of the optical element with respect to beam forming is described, and Grid-FLEET measurements are evaluated relative to the precision of previously described single-point FLEET measurements using Lagrangian tracking for flow in a laminar jet and around a sharp corner. Utilizing a conventional 1-kHz laser source coupled to a high-speed intensified camera, it is also feasible to achieve measurement rates of 100 kHz or higher by mapping the Lagrangian grid to one or more Eulerian measurement points. The data further indicate that enhancement of the instantaneous vector fields and spatial velocity gradients can be analyzed to enhance the understanding of multi-dimensional flow physics in applications in which the use of tracers may be difficult and where multi-directional optical access may be limited.In this paper, we propose a new, to the best of our knowledge, and robust method to optically transmit analog signals in free space through turbid water. In the proposed method, each pixel of original signal is sequentially encoded into random amplitude-only patterns as information carrier. A single-pixel detector is utilized to collect light intensity at the receiving end. To verify feasibility and effectiveness of the proposed method, a number of optical experiments are carried out in different kinds of water conditions, e.g., clean water, water mixed with milk, water with salt, and water with salt and milk. In addition, real seawater samples are also tested. Experimental results demonstrate that the proposed method shows high robustness against different propagation distances through turbid water and resists the effect of various turbulence factors. The proposed method is applicable to transmit information with high fidelity and high robustness against light wave diffusion in free space through complex environment. Furthermore, the proposed method is easy to operate and is cost-effective, which could open up a novel insight into optical signal transmission in free space through turbid water.Here we propose an inverted evanescently-coupled waveguide modified uni-traveling-carrier photodiode (IECWG MUTC-PD) and verify the character numerically. In this photodiode, the epitaxial structure is inverted from p-i-n to n-i-p, and a diluted waveguide is applied. The material of capacitance control layer is optimized to realize energy band compensation and capacitance control. D609 Such structure possesses a large electric field in the whole depletion region and has a uniform light absorption, which improves the space charge effect. As a result, the PD achieves a 3-dB bandwidth of 71.9 GHz with a 35µm2 active area at -5V bias voltage and an internal responsivity of 0.59 A/W in 7-µm long short PD with a 200-nm-thick absorption layer.We numerically demonstrate a Z-shaped metal-based metamaterial to realize an active polarization-controlled plasmon-induced transparency (PIT). The metamaterial unit cell contains two horizontal Au bars and a vertical Au bar. Simply by varying the incident light polarization, a tunable PIT can be achieved due to the reversible conversion of bright and dark modes between the horizontal and vertical Au bars. Moreover, a switchable PIT window modulation can be accomplished via changing the geometrical parameters, and the theoretical fittings according to the coupled Lorentz oscillator model display consistency with the simulated results. Our proposed metamaterials provide a promising strategy for fabricating compact PIT devices such as optical switching, sensing, and selective filters.Based mainly on the distributed Bragg reflector (DBR) short linear cavity with a 1.6-cm-long heavily Tm3+-doped germanate glass fiber and semiconductor saturable absorber mirror (SESAM), a compact passively Q-switched single-frequency fiber laser at around 1950 nm is demonstrated experimentally. By comparing pulse characters of Q-switched operations fulfilled via SESAMs with different parameters, a stable output pulse is optimized to deliver a maximum average power of 22.2 mW, a peak power of 0.67 W, and an optical signal-to-noise ratio over 61 dB. Moreover, the repetition rate of the output pulse can be tuned from 92 to 520 kHz with a narrowest pulse width of 64 ns. To the best of our knowledge, this is the first time a 2.0 µm passively Q-switched single-frequency DBR Tm3+-doped fiber laser has been realized, and it shows great potential application in remote sensing, biomedical science, and nonlinear optics.In this work, a new, to the best of our knowledge, full double-pass serial hybrid fiber amplifier is simulated on OptiSystem 7.0 software. A wideband flat gain spectrum covered both conventional and long communication bandwidth (C+L) from 1530 to 1590 nm, which is approximately 60 nm with high average gain of 23.6 dB; acceptable noise figure of 7 dB is achieved via the L-shape configuration. The main innovative step in the proposed design is decreasing the cascading amplification effect between the combined amplifiers, by making the individual full double-pass for the input signal in each amplifier stage.The measurement of the diopters of spectacle lenses using an artificial neural network is proposed in this paper. A diopter is measured by obtaining the distances between the spots imaged by a charge-coupled device (CCD) during a Hartmann test. Backpropagation (BP) and a radial basis function (RBF) algorithm are applied to train the BP and RBF neural networks, respectively. A set of -20D to 20D spectacle lenses is used to test the proposed method. When comparing the diopter measurement results of the RBF neural network with those of the BP neural network, the former exhibited higher stability and lower errors. In addition, the errors of diopter measurement are not against the system error measured by an auto-focimeter due to the increase of curvature of spectacle lenses. These results indicated that RBF neural network has better performance in diopter detection, and it can overcome the system error caused by the change of lens curvature in auto-focimeter measurement.
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