This PDF file contains the front matter associated with SPIE Proceedings Volume 12343 including the Title Page, Copyright information, and Table of Contents.

Borosilicate oxyfluoride glass with the composition of 50SiO₂-10B₂O₃-13Al₂O₃-14Na₂O-3ZnO-2Li₂O-8CaF₂ (mol%) doped with varied concentration of CeF₃ and/or SmF₃ were synthesized by melt-quenching method, and the corresponding transparent glass ceramics were prepared through isothermal heat treatment at 550°C for 1h. The obtained glasses and glass ceramics were characterized in structure and optical properties. The results show that SmF₃ facilitates the conversion of [AlO₆] to [AlO₄] enhancing the glass network, while CeF₃ mainly results in rupture of tetrahedral network. Doping CeF₃ may affect glass stability in a modest way, while doping SmF₃ may significantly inhibit crystallization. There is obvious energy transfer from Ce³⁺ to Sm³⁺ in a cross-relaxed manner. Rising Ce³⁺ concentration leads to the occurrence of concentration quenching whereas Sm³⁺ emission enhances with increasing concentration at higher critical level. Sitallization improves the luminous efficiency of Sm³⁺ doped glass much more than that of Ce³⁺ doped counterparts due to possible oxidation of Ce³⁺ during the heat treatment.

Simulation studies were conducted on double injector combustion with GO2/GCH4 as the propellant. The effects of different injector spacing on the combustion flow field were compared and calculated using k-ε turbulence models. The results show that the larger injector spacing will increase the thermal load on the front wall of the combustion chamber, but when the injector is close to the wall, the injection fuel will form a protective layer on the front wall and reduce the heat load on the front wall. And the smaller injector spacing facilitates the forward movement of the reaction zone near the axis; Under the condition of small injector spacing, the wall temperature of the rear section of the combustion chamber is higher; A specific inner diameter of the injector has a certain optimal value.

Conventional PID control is widely used in the permanent magnet synchronous motor (PMSM) speed control system because of it is simple to design, but it is difficult to meet the high precision control requirement for controlling the continuous wave mud pulse generator used in the circumstance of downhole. Therefore, an improved exponential reaching law based on the conventional sliding mode control (SMC) is proposed to achieve the purpose of tracking the velocity step signal quickly and accurately. In this law, fractional polynomials containing exponential terms in the coefficients of constant velocity terms is introduced. Simultaneously, to attenuate the influence of chattering phenomenon, saturation function is used to instead of switching function and integral-type sliding mode surface is applied to improve the convergence speed. The simulations show that the proposed improved sliding mode reaching law can effectively improve the performance of control and robustness compared with conventional PID control.

Aiming at the problem of thrust fluctuation during the operation of the electromagnetic pump, a new composite control method is proposed in the control strategy of the inverter power supply. The method adopts a strategy combining repetitive controller and QPR controller. Repetitive controller has a good inhibitory effect on periodic disturbances, and can also improve the output accuracy of the inverter power supply. QPR controller improves the dynamic characteristics of the power system. While ensuring the stability of the system, the output precision of the inverter power supply is improved, which helps to improve the working efficiency of the electromagnetic pump.

As a traditional neutron detector, ³He proportional counter tube has the advantages of high thermal neutron detection sensitivity and good energy resolution. However, due to its high cost, difficult fabrication, and poor anti-interference ability, it is necessary to find better alternative products. In this paper, based on the principle of nuclear reaction neutron detection, a small thermal neutron detector is fabricated by coupling a silicon photomultiplier (SiPM) and a ⁶Li glass scintillator. The characteristics of its output signal are verified by experiments, and the influence of bias voltage and temperature on the output signal is studied. The experimental results show that the detection unit has a reasonable design and can effectively realize the detection of neutrons. The output signal pulse amplitude is -2.80V and the pulse width is 325ns, which meets the requirements of back-end acquisition. With the change of temperature and bias voltage, the noise amplitude of the output signal of the detection unit shows an opposite trend, which provides a solution for the problem of stable operation of the detection unit in different temperature environments.

The study's main goal was to examine the NACA0012 wind turbine airfoil at various angles of attack and velocities while maintaining a constant Reynolds number. The aerodynamic efficiency of an airfoil has a significant impact on the aerodynamic efficiency of a pneumatic wind turbine. The NACA0012 airfoil is thought to be a good wind turbine blade. Calculations about various angles of attack（-10° to 10°）and different velocities from 0.25 to 1.5 meters per second have been carried out to analyze the performance of the NACA0012 airfoil. The results of the CFD simulation are quite similar to the results of wind tunnel testing trials, indicating that CFD analysis is a viable alternative to experimental approaches.

Aiming at the problem of insufficient operation time and deviation of the equipment’s factory evaluation index, the comprehensive performance of the on-site operation of the electricity information acquisition terminal is evaluated and designed in this paper. The performance analysis of the acquisition equipment is completed through the combined device of the nuclear capacity device evaluation structure, and the cluttered information of the acquisition platform is integrated. Use the BF5R feedback line to transfer to the actual power station, responsible for the distribution of the transfer data and the feedback of the information. The DC decoupling improved algorithm is used to realize the billing system of equipment acquisition electric energy, which is used as an important index of the evaluation system. Through the IES VE software to simulate the performance evaluation process of the equipment, the experiment shows that the maximum collected power of the designed test equipment is 6351.6kWh, the effective operation time is 18.2h, and the accuracy of the evaluation index is 98.5%, which proves the feasibility of the design.

Aiming at the problem of real-time performance of the high-degree cubature Kalman filter (CKF) algorithm in nonlinear systems, the mixed degree cubature Kalman filter (MDCKF) is proposed. The Gaussian approximation filter formulas and sampling rules for third-degree cubature and fifth-degree cubature are presented. The MDCKF uses the different degree cubature rule for the time update process and measurement update process. For more efficient use of measurement information, the fifth-degree cubature sampling rule is utilized in measurement update, while the third-degree cubature sampling rule is applied to the time update process. By simulating the target tracking problem and integrated navigation system, it demonstrates that MDCKF has similar accuracy to the fifth-degree CKF but takes less time. Thus, MDCKF has superior performance in balancing accuracy and time cost.

The design of Si carbon hybrid material with clever structure is considered to be an effective method to improve the performance of Si based anode of lithium-ion battery. Herein, we prepared a Si@SiO₂@C (SSC) composite materials by using Si nanoparticles (Si NPs) as Si source and Neoprene as carbon source. On the one hand, SiO₂ generated during calcination can effectively buffer the volume expansion of Si NPs. On the other hand, the Si@SiO₂ NPs are uniformly encased in flexible and conductive carbon derived Neoprene which can effectively buffer the volume change of Si NPs and accelerate the transport of electrons and ions across the whole electrode scale. After electrochemical testing, the reversible capacity of SSC electrode is 1042 mAh g^-1 after 500 cycles at a current density of 2 A g^-1, and the excellent rate performance of 798 mAh g^-1 can be achieved at a current density of 12 A g^-1. When matched with the LiFePO₄ cathode, the full battery can achieve excellent cycle stability and rate performance.

To date, the best efficiency of organic-inorganic hybrid perovskite solar cells (PSCs) has reached 25.7%, but the volatile nature of organic compounds at high temperature results in their poor thermal stability. All-inorganic perovskites such as CsPbI₂Br, possess excellent thermal stability, but the power conversion efficiency (PCE) of CsPbI₂Br PSCs still lag far behind their organic-inorganic perovskite counterparts. To enhance the PCE of CsPbI₂Br PSCs, an organic ammonium salt, namely benzylamine hydroiodide (BZAI) has been adopted to modify the surface of CsPbI₂Br films. The BZA⁺ can interact with Iˉ and Brˉ on the surface of CsPbI₂Br film to passivate perovskite surface defects. In addition, the BZAI interfacial layer can finely adjust the energy levels of CsPbI₂Br perovskite to match with the hole transporting layer (HTL), and thus reduce the charge recombination at the perovskite/HTL interface. Finally, the PCE of the devices is notably increased from 12.87% to 15.08% after introducing the BZAI interfacial layer, and the device stability in nitrogen environment is also improved.

Arrester is a kind of important equipment for lightning protection of 10kV distribution line, but the number of arrester on network lines is much, and operation and maintenance is difficult. It cannot be used to perform a full-term pre-test in the electrical power arrester. It is not accurately discriminated by the operation state, so that arrester is damaged. The line fault often occurs. In this paper, a state monitoring system for the distribution line lightning arrester is designed, which is mainly divided into a lever sensor and a receiver to achieve fast discrimination of state at a lower cost. Experimental verified that, the sensor can work with long-term stable operation outdoor, which can accurately measure the mA stage current.

The experiments of laser welding 5052 aluminum alloy were carried out, and the effect of adding α-Si₃N₄ particles on microstructure and mechanical properties of the joint was investigated. Some α-Si₃N₄ particles melt and form new compounds with the aluminum matrix during welding. The average tensile strength of α-Si₃N₄ preset joint with the maximum tensile strength of 224.5 MPa was 11.5% higher than that of no-preset joint. As far as presetting α-Si₃N₄ particles was concerned, the enhancement of the joint properties benefited from improvement of metallurgical reaction.

This article presents a novel design of reference optical simulator and physical calibration method for optical performance evaluation of real-time fluorescent quantitative PCR analyzer in order to substitute for traditional chemical method. The optical simulator is designed according to the working principle, and technical characteristics such as fluorescence peak height consistency among channels, linear sensitivity factor, fluorescence intensity repeatability, and linear correlation coefficient of fluorescence of real-time fluorescent quantitative PCR analyzer.The calibration results of 5 typical types of real-time fluorescent quantitative PCR analyzers show that the reference optical simulator presented in this article can well simulate different fluorescent dyes. The reference optical simulator can meet the requirements of fluorescent intensity calibration for real-time fluorescent quantitative PCR analyzers with the advantages of good applicability, high convenience and accurate and reliable measurement results.

The photocurrent output of the prototypical photovoltaic CH₃NH₃PbI₃ perovskite strongly depends on the photocarrier generation and dynamics in its optically excited phase. Here we reveal quantitative enhancement in the inter-band continuous absorption beyond free carriers by the Sommerfeld factor in the direct bandgap CH₃NH₃PbI₃ perovskite. High-quality CH₃NH₃PbI₃ single crystal with atomically flat pristine surfaces exhibits doublet photoluminescence as a function of photon energy that is attributable to surface-specific and bulk-dominated luminescence. Exciting power-dependent bulk photoluminescence shows remarkable excitation threshold and optical hysteresis. Bulk photoluminescence decays following a two-stage histogram, i.e., an early stage featured by multi-exponential decaying and a later stage featured by mono-exponential decaying. Taken together, the excitation threshold, the optical hysteresis, and the two-stage time-resolved bulk photoluminescence histogram provide plausible indications of phase evolution and electron-hole droplets nucleation in optically excited room-temperature CH₃NH₃PbI₃ single crystal.

An experimental system was established to study the 12kW fiber laser irradiation effects on thin LY12-CZ plate. The laser spot on the plate, the change of surface morphology, the change of rear surface temperature as well as the penetration time of the plate were measured. During the laser irradiation, the phenomena of bagging, necking, and perforation were observed on the thin aluminum plate in the irradiated area, which was collectively referred to as the "bagging" effect. In our view, the "bagging" effect is related to the two oxide films formed on the front and rear surfaces of the thin aluminum plate. And a model of molten aluminum flow in a sandwich structure was proposed to analyze the mechanism of the "bagging" effect. The measurement results of the two-color radiation thermometer and the time-of-penetration detector were also consistent with the model and the "bagging" effect.

We explored that the radiation resistance of erbium-doped fiber (EDF) and bismuth/erbium co-doped fiber (BEDF) through detecting the radiation induced attenuation (RIA) and the fluorescence intensity. Under the radiation of 0-1.5 kGy, the RIA of BEDF is lower than that of EDF, and especially at the radiation doses of 1.5 kGy the difference reaches 2.949 dB/m at 1300nm. In addition, pumped by a 980 nm laser with 1050 mW, the fluorescence intensity of irradiated BEDF at 0.3-1.5 kGy is higher than that of the non-irradiated one, whose tendency is completely different with EDF. Compared with EDF , the RIA is reduced by 57% after the radiation doses of 1.5 kGy, which shows that doping bismuth ion can significantly improve the radiation resistance of EDF.

The development of methylammonium lead iodine (MAPbI₃) is limited by its low stability in humid environments. Here, the stability, electronic structure, and optical properties of MAPbI₃(001) surface substituted with alkali metal during the adsorption of water molecules were investigated by first-principles calculations. The results show that MAPbI₃(001) surface is more stable after doping with K, Rb, and Cs. It is found that the adsorption of water molecule by Pb atom on MAPbI₃(001) surface is weakened due to K, Rb, and Cs doping, which further enhancing the stability of MAPbI₃ in humid environments. Furthermore, the K, Rb, and Cs dopants reduce the band gap of MAPbI₃ and improve the electron leaping ability of MAPbI₃, among which the gain effect of Cs dopant on MAPbI₃ light absorption is the most noticeable. These findings illustrate the protective mechanism of alkali metal doping on MAPbI₃ in a humid environment. And it may provide theoretical guidance for improving the stability of perovskite solar cells in a humid environment experimentally.

In this paper, a novel microwave bandpass filter with L-shaped structure is introduced, which belongs to a kind of artificial surface plasmon polaritons (SSPPs) type microwave bandpass filter. The filter adopts a symmetrical three-stage structure. The first section is a slot-line waveguide section, which realizes the input/output of microwave signals. The second section is a transition section, which adopts the impedance gradient structure to achieve a good connection with the third section. The third section is the SSPPs section composed of periodic symmetric trapezoidal groove structure and 90 degree bend structure. The passband width and stopband characteristics of the filter can be adjusted by adjusting the geometric size of the trapezoidal groove and its air gap, also the microwave subwavelength binding effect can be further improved, which makes the SSPPs filter more excellent in resisting spatial electromagnetic interference. The filter can be used in L~S band civil microwave communication system.

This article presents a novel design of reference light source and physical calibration method for optical performance evaluation of micro-plate chemiluminescence analyzers in order to substitute for traditional biological and biochemical methods. The reference light source is designed according to the working principle, and technical characteristics such as repeatability, stability, interference among wells, differences among channels and linearity of micro-plate chemiluminescence analyzers. The calibration results of 4 typical types of micro-plate chemiluminescence analyzers show that the reference light source and physical calibration method presented in this article can well simulate different chemiluminescence reagents and meet the requirements of luminous intensity calibration for chemiluminescence analyzers with the advantages of simple structure, good applicability, low cost and accurate and reliable measurement results.

Color Structured light is one of the important methods to obtain 3D information. Although it has the advantage of high efficiency, its reliability is easily affected by the ambient light and the color shape of the object to be measured. In this paper, the reason of low coding reliability is studied. Aiming at increasing the coding reliability of structured light, convolutional code is introduced into structured light three-dimensional measurement system to improve the reliability of system measurement. A new kind of color-coded structured light pattern is generated by combining convolution code with Gray code, which has the ability of correcting error bit at any position and has a relative high efficiency. In addition, the maximum likelihood decoding method using Viterbi algorithm is introduced as decoding method for convolutional code. Finally, the effectiveness of the coding and decoding scheme is proved by simulation experiments.

As the industrial demand for micro energy storage devices increases, the efficient preparation of micro-supercapacitors has become a focus. Here we demonstrated a one-step, high-precision and high-efficiency processing method for the preparation of micro-supercapacitors. The graphene/RuO₂ micro-supercapacitor was successfully fabricated by means of a spatially shaped femtosecond laser method, with a single spatially shaped laser pulse capable of processing an area hundreds of times larger than that of the initial Gaussian laser. The prepared single graphene/ RuO₂ micro-supercapacitor exhibits excellent capacitance (66.4 mF/cm² and 221.5 F/cm³). This method enables high precision and high efficiency processing of composite micro-supercapacitors, which has high potential for industrial.

Quantum dot materials are widely used in infrared photodetectors, solar cells, optical fiber communication and other fields due to their unique advantages. These devices cause the gaps between quantum dots to be occupied by short-chain organic ligands, which limit the transport of charge carriers between quantum dots, and often exhibit lower response and poorer performance. In order to solve these problems, this paper starts from the preparation of lead sulfide quantum dot field effect devices, uses different ligands to modify the surface of lead sulfide quantum dots, and studies the influence of different ligands on the electrical properties of lead sulfide quantum dots. Combining plasmonic nanostructures with semiconductors is a reliable way to improve the performance of various optoelectronic devices. On this basis, this paper studies high-performance photodetectors with different structures from the design point of view, using double-layer structures to improve the structure of infrared photodetectors. The responsivity, specific detection rate, photosensitivity and other properties of infrared photodetection devices based on lead sulfide quantum dots are improved, which has certain theoretical significance for the construction of new nanoelectronics and optoelectronic devices.

High sensitivity fiber optic pressure sensor is in great demand in in all aspects due to its advantages. However, the current high sensitivity optical fiber pressure sensor has the problems of large size and high cost. An optical fiber pressure sensor based on all-silica Fabry-Perot interference has been proposed in this paper. The sensor consists of single mode fiber, silica capillary and diaphragm made of coreless optical fiber. The diameter of the sensor is only 125 μm. With precise control of diaphragm thinning, the diaphragm thickness of F-P sensor is only 1.477 μm, the sensor manufactured in this way has sensitivity with 12.586 rad/MPa. The sensor is ease of manufacturing and low cost. Static calibration shown the advantages of the sensor are high sensitivity, good linearity, repeatability, reliability and low hysteresis.

Ultraviolet (UV) light source has very important applications due to its high single photon energy, short laser wavelength and low thermal effect during processing. A high-performance way to acquire UV light source at 355 nm is using sumfrequency method. CsB₃O₅ (CBO) crystal is a good UV nonlinear optical (NLO) crystal, it can be used to generate UV laser. We acquired high output power UV picosecond (ps) light source at 355 nm through sum-frequency method based on type II phase-matched CBO crystal. As the 1064 nm laser power was 84.8 W, a 30.3 W of 355 nm UV light source with a repetition rate of 600 kHz was achieved. The optical conversion efficiency from the infrared fundamental laser to the UV third-harmonic laser was up to 35.7%. We measured the power stability of the 355 nm UV laser at the maximum power of 30.3 W. The root mean square (RMS) value of the power instability was 0.386% for about thirty minutes. These findings reveal that CBO crystal has great potential in the application of ultrafast UV light source generation with high power.

We propose a compact PBS in the ultra-thin Si3N4 platform based on a subwavelength grating (SWG) waveguide-assisted three-waveguide directional coupler. Compared with the two-waveguide directional coupler (DC), it has a larger supermode effective refractive index difference, so it can significantly reduce the beat length of TE and TM polarization coupling. In addition, by replacing one of the dielectric waveguides with a subwavelength grating waveguide, the beat length of TE polarization coupling can be exactly twice that of TM polarization. The coupling region length of our proposed PBS is only 190 μm. In the bandwidth from 1480nm to 1600nm, the insertion loss of the PBS for TE and TM polarizations are both less than 0.41 dB, and the polarization extinction ratios are higher than 15 dB.

With the increasing integration of optical devices, the requirements for couplers are becoming higher. Nowadays, the couplers not only need to achieve high coupling efficiency, but also achieve a small footprint. In this paper, we propose a broadband and compact edge coupler based on silicon nitride. High coupling efficiency and small footprint can be achieved through a non-linear taper consist of five silicon nitride segments. Aiming at the problem that many relevant parameters introduced by the introduction of five segments and it is difficult to optimize, we select different parameter scanning ranges through the characteristics of different change rates of effective refractive index in different width ranges. So as to design a coupler with high coupling efficiency and small volume. The total length of the coupler is only 91 um, and the coupling efficiency can reach 92.24%. Furthermore, the proposed coupler model has good performance in 1270-1330 nm bandwidth, and the difference between the maximum and minimum coupling efficiency is only 2.48%. At the same time, the 1dB error tolerance of the model can reach 1000 nm.

The Modulation Transfer Function (MTF) is an analysis method of a telescope in the frequency regime, which can estimate the telescope imaging effect through spatial resolution power. Traditional detecting ability studies on a telescope is based on the signal-to-noise ratio (SNR). This cannot analyze the factors affecting detection ability and spatial resolution simultaneously, such as the atmospheric coherence length, the image motion and the aberrations. A new method on the detecting ability evaluation of a telescope is presented in this article, which is based on SNR and MTF. It can compensate for the deficiency of the traditional evaluation method, and can analyze the effective of image motion, aberrations and atmospheric coherence length. It can also be used to analyze a telescope with an adaptive optics system. The simulation results indicate that the detecting ability of a telescope is influenced serious by an image motion, some aberrations or the atmospheric coherence length. The detecting ability reduces about 0.5 magnitudes by image motion, which can improve 1 magnitude through an adaptive optics technology.

Vector beam lasers are highly desirable for wide applications ranging from manipulation to communications. In this paper, we report the first directly modulated vector beam laser with azimuthally polarized emission. It’s a microcylinder cavity added with proper second order grating on the top, which enables single-mode lasing and efficient surface emission. Through theoretically and numerically analysis, the lasers are designed in detail. With optimized top grating, the emission is azimuthally polarized vector beam.

Negative feedback avalanche diode (NFAD) has the advantages of fast quenching speed, low afterpulsing and easy integration. It can be used in quantum communication, fluorescence spectrum detection, single-photon counting imaging and other applications. The research on NFAD devices and their application in single-photon detecting system has thus been of great significance. This paper describes the novel design of NFAD, and reviews the development and application of NFAD devices in recent years. By monolithically integrating a film resistance onto single photon avalanche diode (SPAD), the formed self-passive quenching circuit in NFAD brings about improvements in especially afterpulsing, and effectively enables photon number resolution. Further hybridizing active quenching circuit, the single-photon detection system composed of NFAD performs much better than that of conventional SPAD. NFAD demonstrates more practical application potential so that it will be much more powerfully developed in the future, as we prospect finally in this paper.

Aging of insulation sheath material of power transmission line could damage the performance of insulation cable, causing potential safety problems. In order to study aging characteristics of the insulation sheath of power cable, we present a method to characterize the aging state of cable insulation sheath based on terahertz time domain spectroscopy (THz-TDS). The relationship between the aging degree of the insulation sheath and the absorption coefficient under the terahertz transmission mode is proposed by analyzing the terahertz transmission spectrum of the insulation sheath. The results showed that the cable insulation sheath with different aging degrees have different absorption characteristics in terahertz band, and the absorption characteristics and absorption coefficient were increased as time extended. Aging of insulation components in power transmission equipment is difficult to evaluate by conventional methods, which led to potential safety hazard of power facilities, especially in the long-term operation of power cables. The results showed that terahertz wave was precision in measure of aging characterization of power cable insulation, and it could play a great role in aging measurement of power cable insulation.

Understanding the variation of optical properties of polarized light transmitted in haze media is the basis of polarization imaging detection of targets in haze environment. Aiming at the atmospheric environment with different levels of air quality divided by PM2.5 concentration, this paper studied the correlation between air quality factor and optical depth by measuring the change of light intensity before and after transmission of polarized light. Then, a 532nm laser and a polarization state measuring instrument were used to measure the polarization degree after passing through the haze medium. On this basis, the change of polarization degree of polarized light passing through different levels of PM2.5 atmospheric environment is studied. The results show that the polarization degree has the same trend with the increase of optical depth in the air quality grade of good and mild pollution grade.

To study the effects of the semiconductor structure of the HgCdTe detector by high-energy pulsed light irradiation, building 2D models to simulate the changes of the internal temperature and the structure of the PN junction of the HgCdTe chip after being irradiated by a high-energy pulsed light with wavelength of 1064 nm. Simulation results show that after being irradiated by a high-energy pulsed light, the PN junction of the detector chip will disappear briefly, at the same time, a high temperature is generated on the illumination surface of the chip, and a temperature difference is formed inside the chip. After the laser irradiation, the temperature difference inside the chip changes the distribution of the carriers, creating a temperature difference electromotive force, offsets some of the built-in electric field in the PN junctions, deviating the HgCdTe detector from its normal operating state.

Nonequilibrium electron distribution in copper films is induced under femtosecond laser irradiation. The ultrafast electron dynamics is studied by pump and supercontinuum white light probe technique of transient reflectivity. Measurements of thin films with two thicknesses in the range of electron ballistic length are conducted. We observed faster rise and longer tailing of electron dynamics trace in thinner film, in contrast to results of some previous studies, which could be attributed to weak heat transfer across the interface induced by glass substrate.

A new phenomenon was discovered in the experiment of the HgCdTe detector irradiated by the laser, namely the photoinduced latch-up effect. Based on this phenomenon, a two-dimensional simulation model of laser irradiation on the detector chip was established by using COMSOL Multiphysics simulation software. The carrier concentration distribution, photo-induced current, and temperature in the photosensitive chip were simulated after being irradiated by a single-pulse laser with different power to explore the principle of the latch-up effect triggered by the laser. The research shows that there is a PNPN structure in the photosensitive chip, with parasitic bipolar transistors PNP and NPN. Both parasitic transistors are turned off if the photosensitive chip is working normally. A large number of photo-generated carriers are generated when the photosensitive chip is irradiated by a high-power pulse laser, and the two parasitic transistors are triggered to conduct and form a positive feedback loop, resulting in a large current and triggering the latch-up.

In order to work out the problems in low light efficiency, bad thermal performance and limited operating distance , a hard light dazzler based on the high-power HID lamp is studied in this paper. By means of the optimization of spot size, stroboscopic control and light efficiency, the illuminance, the beam-divergence angle and the heat dissipation are improved a lot, which is verified in tests. With the characteristics of flexible mounting and convenient operation, the hard light dazzler has already been widely used in some harsh environments such as ships, islands and reefs.

In the fields of ultra-wideband satellite communication, integrated radio frequency, radar and other national defense and military at present, it is necessary to realize the interconversion between baseband signals and radio frequency signals in Ka or even U band and L band to meet the processing requirements of RF front-end. Traditional electronic technology usually uses multistage local vibration mixing to realize frequency conversion, which is complicated and accompanied by serious nonlinearity and noise accumulation. As a kind of multi-wavelength light source, optical frequency beam can provide stable multiple local oscillations in the optical domain, and move the baseband/RF signals to the optical domain to achieve flexible mixing processing. In this paper, an UWB microwave photonic mixing technology based on optical frequency comb is innovatively proposed. UWB octave-spanning up-conversion from 10MHz to 60.01 GHz and down-conversion can be achieved by using only 20 GHz microwave driver, which effectively improves the RF preprocessing capability of UWB transmitter in the field of national defense and military.

Photoelectric interferometric laser ranging method is so far at home and abroad developed earlier and has been used in the actual laser spectrum research, and it is another new physical spectrum ranging method research method. The emergence of laser detector system is also promoting the development of modern photoelectric interference ranging laser instruments at home and abroad. Laser detection instrument has a series of new characteristics, such as stronger spectral direction performance, higher brightness level, good monochromism, suitable for modern photoelectric interference laser ranging technology important detection light source. Pulse laser method ranging principle based on pulse laser measurement method is the world’s earliest industrial technology application. The phase laser rangefinder has many main advantages such as smaller volume and light weight than the measuring instrument, and the dimensional accuracy error of the measuring object is directly independent of the range of laser measurement. It can be gradually expanded from practical industrial applications to other more extensive and complex practical technical engineering fields. First of all, this paper introduces in detail the two common detection methods of laser ranging, pulse method and phase method, and especially introduces and analyzes the measurement principle of pulse phase method of laser ranging method. Through many years of phase laser distance measuring instrument applied theory analysis and research, design and manufacture a kind of high precision phase method based on CPLD technology, laser automatic range receiving system, gives the block diagram of the system of specific system model and its system of transmission of the different system modules of photoelectric receivers with computer hardware circuit diagram. The test module system structure in the main circuit components structure include frequency pulse source system and its pulse generating circuit, modulation of the laser signal amplifier and drives the laser receiving amplifier circuit, photoelectric signal receiving and analysis of detection circuit, analysis and processing of mixing amplification circuit, with more than ordinary filter circuit, the comparison of the voltage signal amplification detection circuit unit and so on. The frequency measurement system is the first time to use the differential frequency phase detection technology, reduce the frequency of the laser frequency signal measurement, shorten the differential frequency measurement period, reduce the frequency phase detection error, improve the frequency precision of the laser frequency signal measurement system. Finally, the error in the system is analyzed theoretically, and the concrete solution is given. The deficiencies of the system are analyzed and the future work is presented.

As the main component of power generation, the wall thickness of aeroengine turbine blade affects the dynamic performance of the whole engine. The accurate measurement of wall thickness is very important in the production process of turbine blade. Based on the point cloud processing technology, aiming at the point cloud of blade tip groove obtained by optical focusing scanning, this paper simplifies and denoises the data through two steps of random sampling filtering and statistical filtering, fits the blade tip plane model, projects the point cloud onto the two-dimensional plane, extracts the boundary points of the plane point cloud by the concave envelope algorithm, selects the initial points and initial vectors, calculates the connecting distance of the boundary points, and completes the calculation of the wall thickness of the blade tip.

Single-photon emitters (SPEs) are key to quantum computation and quantum communication, which have been demonstrated in various two-dimensional (2D) materials. In particular, atomic defects in hexagonal boron nitride (hBN) exhibit the characteristics of a typical SPEs at room temperature, drawing great interest due to their potentials in quantum information and photonic applications. This paper reviews the synthetic methods to effectively obtain hBN thin films and deterministically fabricate color centers in 2D hBN. We further introduce their fundamental applications in several fields, such as coupling of surface plasmon to nanowires for quantum integrated circuits and nanoscale sensing. At last, we also discuss the challenges in this field and prospect their future applications.

We propose a generation method of higher-order orbital angular momentum (OAM) based on the cascade of two fabricated lower-mode selective couplers (MSCs) with a home-made four-mode fiber (4MF) and a ring-core fiber (RCF). This all-fiber OAM (also called optical vortex beam, which has a spiral phase wavefront) generation technology has the advantages of simple structure and low cost, which is suitable for the field of vortex-optics fiber communication.

Many optical telescopes have been used to observe cosmic rays, with small-aperture telescopes for gamma photons in the high-energy band and large-aperture telescopes for gamma photons in the low-energy band. Here, we will choose a telescope with an aperture of 6 m to observe gamma rays in the ultra-high energy range. The reflector of the telescope is designed by Davies-cotton. The radius of curvature of the telescope is 16 m, the focal plane is located at 8 m, and the half width of the spot expansion is 10 mm.

Graphene materials prepared by traditional process have the disadvantages of grain boundary defects and uncontrollable parameters, which limit the application of graphene materials. However, laser processing technology has the advantages of no specific environmental conditions and can be combined with computer programming control. It can make up for the shortcomings of traditional technology and is of great significance to the production of graphene materials and graphene based electronic devices. In this paper, the research progress of laser reduction graphene oxide process in flexible electronic skin is reviewed, and its future development is prospected.

In response to the harsh environmental conditions and the strict requirements for payload mass of the airborne platform, a structural design method is proposed for a good performance stability, lightweight and miniaturized laser expander system. In order to realize the lightweight and miniaturization design of the laser expander system, a miniaturized coaxial catadioptric defocus optical system is designed consisting of mirrors and lens. To ensure the stability and lightweight of the structure, the flexure and the main support structure which combined the thin-wall cylinder and truss are designed for the mirrors and lens. Finally, the engineering analysis of the system is carried out. The results show that the relative decenter and spacing between primary mirror and secondary mirror are 2.28μm and 5.92μm under normal working condition, respectively. The maximum surface shape error of the mirrors is 5.42nm. The first-order natural frequency of the system is 349.6Hz, and the maximum value of the root-mean-square of acceleration response under random vibration excitation occurs on the primary mirror, and the amplification factor is 7.1. It meets the mechanical performance requirements of airborne platform.

Fatigue failure is a very common form of fracture failure for metallic materials, which can have harmful effect on the safe service of the material. In recent years, many studies have been carried out to improve the fatigue properties of materials and prolong the service life of metallic components by using different methods. Particularly, laser surface treatment technologies have been widely studied and applied in engineering due to their advantages, which can improve fatigue properties of materials by strengthening the original specimens and healing the specimens with certain damage or microcracks. This paper introduces the research status and reviews the achievements of several laser surface treatment technologies in previous research on material fatigue. In addition, the further research directions of laser surface treatment technologies in material fatigue are proposed.

With the continuous improvement of the level of science and technology, conventional substations have basically realized the digitization and intelligence of inspections, and photovoltaic power stations need to be at the forefront of development. At present, there are still some photovoltaic power plants that have not yet gotten rid of the shackles of the traditional inspection mode, which restricts the development of photovoltaic power plants. Therefore, in order to promote the intelligent inspection process of photovoltaic power plants, a targeted inspection robot overall framework was designed, including integrated functions such as navigation, observation, and robotic arms. And a simple test was carried out by means of a comparative test, which affirmed the capability and economic advantages of the inspection robot in the photovoltaic power station, which can be vigorously promoted and applied. It can be seen that through this research, favorable conditions are provided for the digital transformation of the substation business.

An electrochemical descaling system was established to study the treatment effect of electrochemical descaling technology on the drainage of the cooling system, and the orthogonal analysis method was used to study the effects of reaction time, current density, plate spacing, conductivity of raw water and hardness of raw water on scale removal effect of the system. The results showed that under the experimental condition, if the scale removal amount and the energy consumption per unit scale were taken as the evaluation index, the main factors affecting these two indicators were hardness, conductivity, current density, and finally the plate spacing. The experimental results show that the application of electric softening technology in the field of descaling treatment of cooling system drainage was feasible.

Formation control is the basis for the UAV swarm system to complete the task efficiently. During the flight of UAVs, due to the limits of maneuverability and flight performance, there is a phenomenon of state saturation, which has an extremely important impact on the stability and accuracy of UAV swarm formations. Aiming at the saturation of speed, acceleration and angular velocity in the process of UAV formation, this paper proposes a fixed-wing UAV formation flight control strategy under the condition of state saturation constraints. First, the three-degree-of-freedom dynamic model of the fixed-wing UAV with decoupling of lateral and longitudinal motion is used. The formation control law of the fixed-wing UAV under stateless saturation is designed based on the consensus algorithm. Then, considering the state saturation of the UAV's speed, acceleration and angular velocity, the feedback signal generated by the control law is constrained to adjust. The Lyapunov function is designed to prove the convergence of the formation control strategy. Finally, the effectiveness of the control strategy is verified by simulation.

This paper studies the stability of special high-dimensional discrete-time systems with a single delay. It considers delay effects and characterizes the delay set for the stability of the systems. Results obtained in this paper are as follows. First, a sufficient condition for the delay set to be the whole set is established. This condition is given via matrix norms. Secondly, the delay set are presented for fully coupled high-dimensional systems. The above results are novel and will help to solve the well-known delay margin problems for stabilization and consensus control.

Aiming at the Superbuck circuit applied to the Battery Charge Regulator (BCR) of the space Power Conditioning Unit (PCU), the damping network is connected in parallel with the middle capacitor to eliminate the RHP zeros and improve the characteristics of the high order converter. The small signal model of the system was established through the time-average model, and the double closed-loop control strategy of peak current control was proposed based on the constant current charging mode. Then, the bode diagram of the transfer function was obtained in Simplis simulation software. Finally, the experimental platform of Superbuck circuit was built, and it is proved that the Superbuck circuit with damping network has good steady-state and dynamic performance under the proposed control strategy.

An observation estimation for a kind of semilinear parabolic system is considered in this paper, which is used to solve the time optimal control problem of the parabolic system indirectly for the functional f is globally Lipschitz continuous such that the controllability of the semilinear parabolic system (1) is equal to the null controllability of its linearized system (3). Therefore, the semilinear parabolic system firstly needs to be linearized according to the property of the functional f. Secondly, to get the main estimation of the linearized system (3), two lemmas about the linearized system (4) are listed, which are used to prove the main estimation which will be used to show the null controllability of linearize system (3). At last, the observation estimate for the linearized system (3) is shown by the two lemmas and several classical inequalities.

With the improvement of chip debugging technology performance, the chip physical attack technology has also been developed rapidly. At present, the active shield has become the main protection against physical attacks on the chip. In this paper, for the shortcomings of digital shield detection circuit which cannot resist rewiring attack, we propose a scheme to collect some channel signal propagation delay to detect whether the shield is under rewiring attack on the basis of random code stream detection circuit. The scheme is applicable to parallel multi-channel shields. Random sequences is passed to the inner channels and pulse signals is passed to the outer channels, and the random sequence is compared in the detection circuit to determine whether the random sequence is consistent and the pulse signal width is within the error range, so as to determine whether the shield is damaged or modified. The final experiment shows that the scheme has the characteristics of simple digital type detection circuit, low overhead, after the implementation in smic0.18um process, the area of 25766um², power consumption of 1.6639mw, can identify more than 8% of the shield failure area of rewiring attacks, to make up for the inherent parametric type detection circuit complexity defects.

Based on the TC9400V/F conversion chip, a moisture detection system for grain dryers is designed. The system is based on the CC2530 chip to build the ZigBee coordinator and the wireless radio frequency module of the terminal node. Converted grain moisture content into pulse signal output by TC9400 capacitive sensor module. The coordinator receives the frequency data collected by the terminal node. At the same time, a PT100 temperature measurement module is added to compensate the system temperature. After the coordinator processes the data, the grain moisture and temperature values will be sent to the host computer by the RS-485 circuit, and finally realizes the wireless detection function of grain moisture. The test shows that the error of the moisture content measured by this system is within 0.5%, which fully meets the requirements of using.

This letter proposes an improved method to estimate intermediate frequency (IF) signal frequency of FMCW LIDAR. This method extracts characteristics of IF signal from FMCW LIDAR and optimizes the selection and solution of intrinsic mode functions (IMFs). The main contribution of the proposed solution, namely refined modal variation Hilbert-Huang transform (RMV-HHT), relies on the extraction of characteristics from the specific IMF of the IF signal decomposed by variational mode decomposition (VMD). Considering non-stationary interference and environmental noise, the RMVHHT and four competitive methods are evaluated. Calculating distance after signal processed by different methods, the RMV-HHT achieves the highest SNR and lowest mean absolute error at different distances. Results demonstrate that the proposed RMV-HHT method is superior to traditional methods in FMCW LIDAR signal processing.

Matched uncertainty can negatively impact the expected stability and performance characteristics of physical systems. To solve this problem, this article puts forward a fractional-order model reference adaptive controller for a class of multi-input multi-output systems with matched uncertainty. We further show that all the signals are bounded and the mean value of the squared norm of the error converges to zero with the fractional-order Lyapunov technology. A fractional wing rock aircraft system with matched uncertainty is demonstrated.

The stochastic volatility of photovoltaic power generation and the high energy storage cost are the main factors that restrict the large-scale development of photovoltaic power generation. Aiming at the problem, the adaptive wavelet packet decomposition based on the photovoltaic grid-connected power limit requirement is used to analyze the photovoltaic power, and the multi-type energy storage system is used to smooth the power fluctuation component. In this paper, the operating state of the energy storage element is fully considered, and the energy conservation, state of change (SOC), and power constraints are used as constraints to establish an energy storage load distribution model. The example analysis proves that the proposed method can effectively smoothing the fluctuation of photovoltaic power and improve the economics of energy storage system. It has certain practical significance and reference value for practical engineering applications.

Aiming at the current electricity theft behavior in the power system, this paper proposes an analysis method of electricity theft behavior based on the time and space dimensions. In the spatial dimension, the outlier algorithm is used to analyze user behavior. Then, for users whose spatial dimension analysis results are normal, the time dimension analysis method is used for further analysis. Finally, an association matrix is constructed to find out users who are suspicious of stealing electricity. This article analyzes the power theft behavior in the power grid and finds out suspicious users, which is of great significance to the adjustment and optimization of the power grid structure.

Maximum power point tracking (MPPT) is the key to improve power generation efficiency in photovoltaic power generation system. In this paper, the photovoltaic cell model is established in Matlab/Simulink platform, and the output characteristics of photovoltaic cells under different light and temperature are simulated and analyzed. In order to solve the problems of misjudgment, oscillation and tracking velocity of traditional perturbation observation method , a control strategy with variable step size disturbance observation method is proposed. The simulation results show that the improved disturbance observation method has good dynamic tracking speed and steady-state tracking accuracy, and can effectively eliminate the shortcomings of fixed step disturbance observation method.

Accurate calibration of image acquisition and projection device in fringe projection measurement system is the basis of system work, and the calibration accuracy of the parameters directly affects the measurement accuracy of the system. An improved projector calibration method is proposed. Using a high-precision circular calibration plate, the camera is calibrated by Zhang Zhengyou's calibration method and nonlinear optimization; using the vertical and horizontal two sets of grating images projected by the projector, the corresponding relationship between them and the camera image is established, and then the center of the mark point in the projection is obtained. Then use the camera model with radial distortion to calibrate the projector; analyze the phase error when the projector is calibrated, and use the improved multifrequency fringe phase shift method to reduce the error; finally, through the calibration and the three-dimensional measurement experiment verifies the method in this paper. The experimental results show that the calibration method in this paper is simple in operation, high in precision and wide in application.

In omnidirectional/directional MMW radar multi-data fusion for road network operation monitoring technology, as the vehicle will be obscured while in motion. It causes the MMW radar sensor to fail to scan and detect the corresponding vehicle for a short or long period of time. This phenomenon can make the system unable to continuously track and locate a particular vehicle. Therefore, the paper investigates the compensation method for vehicle monitoring when obstacles and vehicles are obscured based on omnidirectional/directional MMW radars multi-data fusion, and proposes for the first time an omnidirectional/directional MMW radar vehicle breakpoint inertia compensation technique to pre-determine the trajectory, driving status and position of the lost vehicle. This ensures that in the event of a temporary loss of this target information, the data remains coherent and unchanged. The technical difficulties of obstruction and vehicle obscuration on highways are solved.

Laser thermoelastic actuation is widely used in micro-actuation fields, such as MEMS and MOEMS. The advantage lies in non-contact, non-destructive, easy integration, and mobility. The low energy efficiency of the thermoelastic laser actuation limits its applications in manipulations of millimeters and submillimeters. In this study, we investigate the laser thermoelastic mechanism, and it is demonstrated to be an efficient non-contact way to achieve optical actuation. A millimeter-level nickel cantilever is successfully actuated with large amplitudes (several millimeters) at lower orders resonant frequencies by a nanosecond pulsed laser. The nonlinear modal interacted vibrations of the cantilever are also observed experimentally, the energy transfers from a high-frequency pulsed laser excitation to the low-frequency response of the cantilever. Moreover, we demonstrate that the first-order mode of the cantilever always dominates the nonlinear vibration at far high-frequency excitation, which would benefit the laser actuation control of the cantilever at a higher frequency. Furthermore, this work also presents a laser modulation method for a new widely spaced modal interaction. The results show that the appearance of the low-frequency mode has a slow modulation of the amplitude of the high-frequency mode. This study provides an effective non-contact approach for the optical excitation of the millimeter-level cantilever, empirically investigates the nonlinear features, and enriches applications in fields such as AFM sensing, precise processing and separation of bio-particles/cells, optical manipulation and operation of microrobots, and lab-on-a-chip devices.

In this paper, a simulation experiment is done to study the influence of atmospheric turbulence on the laser beam in the process of oblique transmission. The horizontal random atmospheric turbulence phase screen group is generated by using the power spectrum inversion method plus sub-harmonic compensation method, and the position distribution of the phase screen on the inclined transmission path is corrected by combining the atmospheric refractive index structure parameters that vary with height. Atmospheric turbulence phase screen set suitable for simulating slant laser transmission. Through simulation, the far-field light intensity distribution of the inclined transmission phase screen group and the horizontal transmission phase screen group is compared. The results show that, compared with the horizontal atmospheric turbulence phase screen group that does not consider the atmospheric refractive index structure parameter changing with height, the far-field light spot of the laser beam after passing through the oblique transmission phase screen group is more obvious, and the light intensity attenuation is more serious. The modified slope phase screen group is more accurate in simulating the effect of atmospheric turbulence on the laser beam.

This paper proposes an imaging analysis technique based on a concatenated convolutional neural network to improve and standardize the assessment procedure of laser cleaning 7075 aluminium alloy. First, an orthogonal experiment based on the pairwise algorithm is designed to analyze the cleaning effect variation under different laser processing parameters. Based on the data augmentation of experimental image datasets, sufficient datasets can be input into several deep convolutional neural networks to realize the automatic and quick assessment procedure for laser cleaning quality. The results show that the classification performance of the concatenated network based on Xception and ResNet50v2 networks is best, the average accracy of the proposed network for detecting surface roughness is 99.50%, and the overall average accuracy for all classes is 98.40%.

When shooting macro, the pictures have a very shallow depth of field. The study of this situation has produced results that infinity depth of filed macro lens system without special optical components can be designed. The result can obtain mathematical computing formulas to get the initial structure which can be optimized to achieve infinity depth of filed macro lens such as Jim Frazier lens.

Due to the diversity of underwater environments, it is difficult to test the underwater optical communication systems in actual seawater. This letter uses the Monte Carlo model to study channel capacity of underwater optical communications. Matlab is used to analyze the transmission of laser of various wavelengths in different water and the influence of changes in water quality. Furthermore, the influences of seawater type, divergence Angle, transmission distance and beam type on the power received by the receiver are analyzed when blue-green laser is used as the light source. The experiment shows that in the same water quality, with the increase of divergence Angle and transmission distance, the light intensity received by the receiver becomes smaller and smaller and the photon distribution becomes more and more dispersed. Compared with the Gaussian beam, when the attenuation coefficient is small, the energy of the receiving end is more concentrated when flat-top beam is used as the light source.

In this paper, we design an adaptive underwater wireless laser communication terminal which contains optical unit, acquisition tracking and pointing (ATP) unit, and communication unit. This kind of architecture could achieve automatics alignment, and solve the contradiction of signal receiving due to the saturation of detector power at close range and insufficient power at long range. Besides, the communication rate in this design could be adjusted according to the channel conditions. The communication rate can support 100Mbps at most, and the distance can reach up to 200 meters based on the design.

As a new lightweight material, Carbon Fiber-reinforced polymer (CFRP) has been widely used in various fields, but its difficult-to-machine characteristic also severely restricts its application. In this paper, femtosecond laser with center wavelength of 400nm and 800nm was used for multi-pass scanning processing of CFRP to study the relationship between laser wavelength and processing quality and processing efficiency, and try to obtain smaller heat affected zone (HAZ). The experimental results show that when the experimental conditions are the same, the HAZ obtained by femtosecond laser processing of CFRP with the wavelength of 400 nm is about half that of the wavelength of 800 nm, and the minimum can reach 1.5μm, but the width of slit is smaller than that obtained by femtosecond laser processing with the wavelength of 800 nm. Therefore, reducing the wavelength of femtosecond laser can effectively reduce the HAZ, but at the same time, it will also reduce the processing efficiency.

An acceleration feedback control strategy based on Kalman filter is proposed to further improve the stability accuracy of the airborne laser communication terminals. Firstly, a Kalman filter is designed according to the servo system model of the airborne platform. The Kalman filter is used to obtain the optimal estimation of the system speed and acceleration. Then, the velocity and acceleration estimates of Kalman filter output are used as feedback signals of the speed loop and acceleration loop of the controlled object respectively. Finally, the experimental results show that the servo system with acceleration feedback control can suppress the disturbance torques of different frequencies within 2.5Hz, and the disturbance isolation is better than 25dB. Compared with the traditional single speed loop control scheme, the overshoot of step response is reduced by at least 40%. The introduction of acceleration loop into traditional speed loop control system can effectively improve the servo control performance of airborne laser communication terminals, and has high engineering application value.

Plasmonic colors produced by the resonant interaction between light and metallic nanostructures have been extensively studied. However, the current manufacturing methods for plasmonic metasurfaces rely heavily on lithography and templates, which are prohibitive in terms of scalability, process complexity, efficiency, and economy, severely limiting their wide application. In this study, a method to fabricate polarization-sensitive metal-insulator-metal metasurfaces by femtosecond laser-induced dewetting of gold films has been proposed. The elongation direction of the dewetted nanostructures is controlled by the laser polarization. The structural colors formed by the metasurface are sensitive to the polarization of illumination light. By adjusting the laser power and scanning speed, the metasurfaces can appear yellow, red, and green. This method is expected to be applied in anti-counterfeiting and optical multiplexing.

Ultraviolet C (UVC) radiation is an effective method of disinfection in public areas. As an emerging source of UVC, ultraviolet C light-emitting diodes(UVC-LEDs) are practical for the benefits of mercury-free nature, long life span and multiple applications. However, it takes a longer disinfection time using UVC-LEDs result from the low output light power of UVC-LEDs. In this study, a pulsed light (PL) radiated by UVC-LED with increased instantaneous voltage and current was applied for the irradiation of Escherichia coli (E. coli). It demonstrated a nonlinear relationship between the instantaneous power of UVC light and the sterilization effect of E. coli. In addition, the log-inactivation of E. coli irradiated by PL from 10 microseconds at 1kHz during 60 seconds was compared with those irradiated by continuous light (CW) during the same exposed time. The result shown the sterilization of E. coli in PL was more effective than CW during same time.

The grating pitch is an essential structural parameter of the grating. In the precision displacement measurement system, the grating pitch as the measurement reference directly affects the measurement results. In order to ensure the accuracy of the measurement, the grating pitch needs to be detected. Based on the laser interference principle and grating diffraction principle, this paper proposes a new method to convert the grating pitch into interferometer and grating displacement comparison during the grating motion. The experimental results show that the measurement error is less than 1.2 nm and the uniformity error is less than 0.34 for the grating with 833 nm pitch, which verifies the method's feasibility.

Extracting the stripe center during the measurement process can significantly improve the measurement accuracy, and the optical stripe center extraction algorithm is an important factor determining the accuracy of the optical stripe contour location and extraction speed. For the traditional optical stripe center extraction method, because the ambient light conditions will affect the stripe center extraction under certain circumstances, the stripe center extraction often cannot accurately obtain the centerline, and to a certain extent, the extraction time of each algorithm is increased. In this paper, a line laser stripe center extraction method based on channel separation is proposed. The measured area is separated from the background area by the image segmentation algorithm, the Hessian matrix is obtained for each part of the measured area, and its normal direction is determined to obtain the sub-pixel stripe center, which can effectively avoid the problems of high light and certain brightness of the object, improve stripe center extraction speed and reduce stripe center noise.

The phenomenon of branch is often caused by the propagation of matter through uneven media. In the field of optics, it was first discovered in recent years that this phenomenon can be caused by laser beam propagation in soap film media. Soap film media can be regarded as a special "film" due to its fluidity and other characteristics. In this paper, the phenomenon are explained theoretically from two parts: geometry optics and wave optics. Analogy of electromagnetic field, on the basis of the theory of optical waveguide, the theory of electrodynamics and Maxwell's equations for the theoretical interpretation of the phenomenon, and found that the phenomenon means that the light incidents into a medium with a randomly varying refractive index and occurs diffraction, which is due to weak correlation potential function changes caused by wave deflection caused by caustic. Then it is verified through experiments. Finally, it is concluded that the laser beam remains collimated before each bifurcation, and the first bifurcation point is located at the maximum potential energy difference of media. The essence of this phenomenon is influenced by film’s potential intensity and correlation length, incident coherent wavelength and external environment. The soap film concentration, shape and different positions of incident soap film will affect the change of film thickness, which further affects its potential intensity and correlation length. The greater the potential intensity and correlation length results in the more obvious the branching flow phenomenon within a certain range. Beyond this range, the branching flow phenomenon will not occur.

We propose a method to measure the mode coefficient in a few-mode fiber with OAM modes. In this method, the eigenmodes are calculated through the optical fiber parameters, including LP modes and orbital angular momentum (OAM) modes. Using a single spatial light modulator (SLM) to load multi-channel computer-generated hologram (CGH), multiple matched filters can be generated at the same time to realize the real-time and accurate measurement of each mode coefficient (mode content and relative phase) and reconstruct the optical field. We validate the method on multimode beams, and the accuracy of mode coefficients measurement is up to 99%. It can be used as adaptive control coefficient to provide solutions for the expansion of photon lantern and other technologies.

Gain switched semiconductor laser system is a simple method to generate ultrashort optical pulses. It has been widely used in optical fiber communication, precision machining, precision measurement, biomedical and other fields. In order to advance the research on gain-switched semiconductor lasers, the effects of external electrical excitation signals on the optical pulses output from the gain-switched semiconductor lasers (GS-LD) were studied by simulation and experiment. The research included the influence of bias current, power and frequency of the modulation signal on the optical pulse, respectively. In addition, the reasons for these influences were analyzed. Selecting the appropriate bias current and modulation signal parameters can make the laser output high-quality picosecond pulses with narrow pulse width and small tailing. The results and analysis presented in this paper have implications for the study of the optimal operation state of gain-switched semiconductor lasers and subsequent research on it.

A differentiator-based photonic approach for the instantaneous microwave frequency measurement (IFM) using a phase modulator and an optical Gaussian filter is proposed and experimentally demonstrated. A microwave frequency measurement with high resolution is achieved by a monotonous frequency-to-power mapping obtained by differential operation in optical domain. A proof-of-concept experiment has been performed, in which a measurement error less than ±0.1 GHz over the frequency range 0.1-10 GHz with input power of 0 dBm is demonstrated. The measurement error of the IFM system is still less than ±0.24 GHz, even though input signal power decreases to -30 dBm. The approach suggests a potential capacity for integrated IFM by using all-optical computing.

Laser angle and attitude measurement technology has the advantages of high precision, high dynamic and strong anti-interference ability, which makes it show great application value in the field of aerospace. It is widely used in space rendezvous and docking, aerial photography and remote sensing, aircraft attitude measurement and angle sensor calibration. This paper briefly describes the basic principle of laser angle and attitude measurement system, summarizes the current main measurement methods, including the technical research progress based on laser interferometry, laser collimation measurement, vision measurement and laser tracking measurement in recent years, and introduces the application status of laser angle and attitude measurement technology in the field of aerospace, The future development trend of laser angle and attitude measurement technology is prospected.

The solutions for the example basing on the initial velocity, the power ratio about the critical power and the input power, and the ellipticity have been accessed according to solving the cylindric coordinates’ (1+3)D pxi-axis equations. The CAiIG wave packets are attained about the combinatorial solution by the Ince-Gaussian(IG) beams if we get it in the space domain and the Airy pulses with initial velocity if we get it in the time domain.

With the development of extinction materials, various materials suitable for smoke are widely used. Smoke is essentially composed of solid aerosol. The extinction properties of aerosol are affected by diffusion characteristics. Aerodynamics is used to describe the motion of aerosol particles. Normal 𝑘 - 𝜀 model and DPM model are used to simulate aerosol diffusion process in outdoor environment. The diffusion law of aerosol under different wind speed is analyzed. Distribution characteristics of aerosol mass concentration is studied. Combined with Lambert-Beer law, the effective infrared extinction area of aerosol is calculated. The result shows that the wind speed play an important role in aerosol diffusion in the initial state. When the wind speed is near 1m/s, aerosol can diffuse steadily, and the extinction area will show a trend of rise. In addition, the area of effective concentration will not decrease too fast, but will show a trend of slow rise and begin to decline after 30s.

Multi-wavelength laser arrays are critical for co-packaged optical interconnects, dense wavelength division multiplexing, high-performance optical computing, and sensors. Based on the reconstruction equivalent chirp (REC) technique, multiwavelength laser arrays (MLAs) are demonstrated with high channel count and high precision wavelength spacing. Recently, the photonic wire bonding (PWB) technique is applied to connect the MLA. But the lasers are mostly surface-emitted, such as the horizontal cavity surface-emitting lasers. In the practical applications, the lasers are usually edge-emitted, which is more difficult for the PWB technique. By using the photonic wire bonding technique, we connected a six-channel REC-based MLA, a PLC chip, and the fiber array. The lowest total transmission loss reaches to 7.8 dB. With further optimization of the PWB waveguide, the REC-based MLAs can be applied more easily, which is a potential solution for the requirement of high performance multi-wavelength light source in the relevant field.

The defects of shield tunnel segments, such as dislocation, cracking and falling off, are one of the hot research topics in underground engineering. Based on data driven thoughts, the point cloud of shield tunnel is expanded into a binary image. Due to the image contains the mapping topological relationship between the original point cloud and the pixel, the morphological algorithm was used to identify the splice joints between rings, segmentation of tunneling image expansion is realized ring by ring. Then, the laser point cloud data were segmented at the segment scale, and the defects could be identified and detected in the segment. The experimental results show that the proposed method could effectively identify the segment defects.

D-shaped fiber is widely used in optical fiber sensing due to its special structure and excellent performance. Traditional manufacturing methods for D-shaped fiber are mechanical polishing and chemical etching. These methods have some disadvantages, such as low processing efficiency, and introduction of sub-surface damage layers or impurities. Laser ablation technology, as a non-contact high-efficiency technology, has been applied in optical fiber processing. The CO₂ laser was chosen as the heat source due to the strong absorptivity of glass for a laser with a wavelength of 9-11 μm. In this paper, we reported a new method of D-shaped fiber manufacturing based on CO₂ laser and study the effect of processing parameters on the surface morphology.

In order to realize the visible, integrated, and intelligent control requirements of optimal pulsed light, an optimal pulsed light control system for dry eye treatment was designed based on ARM. The system adopts the double-layer structure of Android development platform + STM32 micro-controller, which realizes the isolation of human-computer interaction and component control, and enhances the application expansion function of the system. Relying on the PWM control signal generated by the high-speed clock integrated by the STM32 micro-controller, the output voltage can be continuously adjusted from 200 to 700V; Using the single pulse/pulse cluster signal can realize the precise control of the optimal pulsed light, the specific indicators are as follows: single/double/triple pulse output; sub-pulse width is 0.3, 0.5, and continuously adjustable from 1 to 5ms; sub-pulse interval is continuously adjustable from 1 to 99ms, and the step is 1ms; the frequency in single pulse mode is 0.5, and continuously adjustable from 1 to 10Hz. The system integrates a temperature and humidity module and a micro switch module to monitor the working environment and detect the ready state of the treatment handle in real time. The tests show that the system is reliable and stable in operation, which meets the requirements of control accuracy, and plays a pre-research role for the subsequent extensive application expansion of the instrument.

The Window Fourier Ridge (WFR) is one of the useful methods in local frequency extraction from a fringe pattern. But the background of the pattern and the inherent noises existed in the pattern will disturb the extracted result, which need to be removed before operation. To solve this problem, we modify the WFR method by spectrum normalization of the fringe pattern in its frequency domain. Then, the accuracy of the extracted local fringe frequency is enhanced greatly due to the inhibition of the disturbance from its background. The principle of the normalized spectrum method is detailed by spectrum analysis of the fringe pattern. The conducted simulations and experiment results show that the local fringe-frequency estimated from the fringe pattern with background by the proposed method is as good as that from the fringe pattern without background by traditional WFR method.

This paper used the method of conventional detection and laser tracking method for the 2022 Hangzhou Asian Games rowing and canoeing. The detection accuracy of whole station scanning and laser tracking methods is higher than conventional methods, and higher than conventional and whole station scanning methods, with high detection accuracy and convenient operation. And the coaxial degree of the bottom shaft and the two lock gates were welded, and the test results meet the design requirements.

Weak measurement technology can be used to achieve ultra-precision modulation of variables. Based on this, to achieve precise modulation of beam deflection, we establish a model of beam propagation using weak measurement, theoretically deduce the general formula of the deflection angle, and illustrate the general process of precise modulation of the angular shift of the beam. By controlling the post-selection state of the weak measurement, the angular shift of the beam can be precisely regulated. The deflection angle is proportional to the imaginary part of the weak value. We describe a simulation and discuss how precise angle tuning can be achieved by controlling experimental parameters.

The prominent contradiction between energy and environment has brought new opportunities to the solar thermal power generation industry. Starting from the current situation of solar thermal power generation in the world, this paper briefly introduces the solar thermal power generation technologies such as tower type, trough type and medium type and the research results at home and abroad, analyzes and compares these three mainstream solar thermal power generation technologies, and finally based on the actual situation of our country The problems and challenges faced by China's solar thermal power generation industry are pointed out, and its broad development prospects are put forward.

When compressing massive data, using software implementation of Zstandard (Zstd) algorithm will occupy a lot of processor resources, and it will lead to performance bottleneck due to serial data dependency, hardware acceleration of Zstd algorithm is an effective solution to the above problems. Therefore, in this paper, we propose a hardware architecture for concurrent streaming of multiple hash tables applicable to the Zstd algorithm. Using this design scheme, the RTL-based VCS simulation verification shows that the compression ratio almost reaches the standard of software, the compression speed of hardware is about 5.5 times of software compression speed, and the decompression speed of hardware is about 5 times of software, where the compression speed reaches up to 1.17GB/s and decompression speed reaches up to 1.89GB/s, and compared with the existing hardware implementation of Zstd, the compression speed is about 11.4% higher than that of the existing hardware implementation of Zstd.

Aiming at the problems of fuzzy boundary and color deviation in marine biological images, using the advantages of fast convergence speed and strong optimization performance of mayfly optimization algorithm, an improved mayfly algorithm (RCMA) based on reverse opposition-based learning is proposed in this paper. Firstly, the optimized initial mayfly population is obtained by reverse opposition-based learning to enhance the diversity of mayfly population and improve the convergence speed of the algorithm; Then the linear decreasing weight method is used to update the position of male and female mayflies, which reduces the risk of premature mayfly algorithm and avoids the oscillation phenomenon near the global optimal solution in the later stage of the algorithm; Finally, the double gamma function is introduced, and the improved mayfly algorithm is used to find the optimal gamma value, which is used to improve the contrast of the image and enhance the image. Simulation results show that the RCMA proposed in this paper has a certain enhancement effect.

SRAM PUF is already embedded in MCU as a traditional memory, it can be used as a PUF module without hardware modification and additional hardware overhead. However, due to different working environments such as temperature and voltage, the response sequence generated by SRAM PUF is not necessarily the same for the same excitation. Therefore, the resulting response sequence needs to be processed to get a unique stable key. In this paper, a soft decision fuzzy extractor scheme based on RM cascade code is proposed, and the simulation verification and reliability test are carried out by using the system simulation platform, and the final results show that the error rate is below 0.08, the reliability reaches more than 0.999999, the required SRAM number is reduced to 2464, which is reduced by 47.57％ compared with the traditional hard judgment [12], and the consistency index can reach 99.99 in the temperature range of 20℃~80℃.

With the continuous improvement of the performance of the spaceborne active phased array antenna, the power supply required by the phased array antenna is developing towards low voltage and high current. The efficiency of the power supply is more stringent. This paper presents a design of a high-reliable power supply for space-borne active phased array antenna. This article introduces the composition of the phased array antenna power supply, and proposes a novel high-reliability single transistor forward interleaved parallel topology. The synchronous rectification control technology is adopted to realize the zero-voltage switch (ZVS) of the DC/DC converter, which effectively reduces the loss of the rectifier device and improves the efficiency. Secondly, the maximum current autonomous current sharing technology is used to realize parallel connection of multiple DC/DC converters. Finally, through the results of working waveforms and experimental verification of the engineering prototype, all the requirements are achieved.

Aiming at the sensing, monitoring and control requirements of the belt conveyor equipment in the dry bulk cargo wharf, this study combines the monitoring system with the control system. On the premise of comprehensive sensing of the equipment, by transmitting the signal obtained by the sensing terminal to the central control room, the interaction and linkage between the real-time state of the belt conveyor and the automatic control system of the wharf are realized, and the incomplete sensing of the key equipment of the wharf is solved The belt conveyor intelligent monitoring system not only meets the needs of intelligent monitoring and unmanned monitoring, but also reduces the risk of workers working in complex environment, and fully realizes the goal of safe, stable and efficient operation of the production system of dry bulk terminal.

On the basis of traditional algorithms, facial expression recognition combined with deep learning technology has improved the recognition accuracy and recognition speed in various scenes, especially in several large data sets. However, with the continuous vertical and horizontal expansion of the network structure focusing on the improvement of recognition effect, it has brought the problems of too large network volume, difficult deployment of mobile terminal, and inability to take into account the effect and practicability. Aiming at this problem, we proposed an improved vgg network structure, and processed the network structure, which greatly reduced the amount of network parameters under the condition of improving the recognition accuracy.

At present, with the rapid development of industrialization, construction and real estate industries have also been developed, but the verification and entrance control of vehicles carrying large equipment and cement also need to be checked manually, causing a lot of artificial burden. In this paper, an improved algorithm based on deep learning is proposed to realize unmanned gate detection. The distance between the vehicle and the gate can be judged by real-time detection of whether there is a vehicle passing by, so as to make the instruction of lifting the gate or lowering the gate. Compared with the traditional gate detection, the use of a lower cost of ordinary cameras can be completed, so as to save a lot of cost, and can detect the vehicle information in real time, consistent with China's industrial intelligence strategy. In this paper, YoLoV4 algorithm is used and mobilnet-V3 algorithm is used to replace the original main network structure, which greatly reduces the number of parameters of the algorithm structure and improves the running speed of the algorithm, so that it can reach the real-time state. VOC data sets were used for training and detection, and the experiment proved that the speed was greatly improved and real-time vehicle detection could be realized.

Process controller performance evaluation systems have been widely used in modern industries with increasingly complex control objects. However, there is a prerequisite for their implementation: the models obtained from the system identification are all from the same stable operating conditions, because when the operating conditions are not unique, the performance evaluation strategy cannot determine whether the controller performance degradation is due to real uncertainties or changes in the operating conditions. Therefore, it is necessary to identify the corresponding model according to the specific operating conditions and use it to solve the optimization problem to obtain a specific performance benchmark for accurate performance evaluation. In this paper, we propose an online data modeling strategy based on an improved just-in-time learning algorithm, which proposes an integrated learning framework for similar sample selection using a variety of different similarity measures in the selection of local modeling neighborhoods. Then, the local prediction models are trained, and finally, the final results are obtained by integrating the strategy to synthesize multiple local prediction models. The effectiveness of the proposed algorithm in this paper is demonstrated by Wood-Berry simulation experiments.

For the problem that the basic whale optimization algorithm is easy to fall into local optimization in the later stage, resulting in insufficient solution accuracy, at the same time, in order to improve the solution efficiency of whale optimization algorithm to optimize engineering problems, an adaptive weight whale optimization algorithm is proposed. The improved algorithm introduces weight factor to reduce the problem that it is difficult to jump out of local optimization in the later stage of the algorithm. Balancing the global search ability and local search ability of the algorithm enhances the global search ability in the later stage of the algorithm, and improves the optimization ability and solution accuracy of the algorithm. The improved algorithm and several comparison algorithms are applied to the classical engineering optimization problems. The experimental results show that the improved algorithm has good practicability and universality in solving accuracy, optimization ability and engineering project optimization.

For electromagnetic environment simulation training requirements, through the adoption of digital technology, such as the earth to carry out the simulation of typical area, combat, goal setting and electromagnetic environment simulation by using 3D digital earth system provide the material of electromagnetic wave swept slightly region and elevation data to establish the mathematical model of RCS, enables the pilot to assume that the operational area for simulation training, To be able to better carry out combat training tasks to lay a good foundation.

A three-dimensional omnidirectional antenna in the X band based on ring-mounted monopole antenna is designed. The design scheme adopts a combination of theoretical analysis, simulation verification, numerical optimization and application. Theoretical analysis is carried out by means of model analysis and mathematical derivation, and the HFSS full-wave electromagnetic simulation software is used for modeling and simulation. Optimize the design of antenna parameters by electromagnetic numerical algorithms. The array of antennas is discussed, and the pattern of antennas and reflection coefficients are given. The coverage and symmetry of the antenna pattern are good, and it has the advantages of low cost and simple and easy to achieve the method of antenna array, which has a guiding effect on related engineering practices.

This paper intends to develop an intelligent unmanned warehouse based on the Internet of Things. Through the combination of informatization, Internet of Things and mechatronics, multiple logistics forklifts can run at high speed at the same time, greatly improving the operation efficiency and accuracy, and reducing the cost of warehouse management. The automatic logistics forklift is based on the powerful processing capability of STM32F767 to perform arithmetic processing on the logistics network, and guide the automatic logistics forklift to complete accurate high-speed movement according to the laid signals. At the same time, the intelligent unmanned warehouse uses the Internet of Things technology to obtain the logistics forklift. In order to handle the real-time status of warehouse goods, completely unmanned transportation can be realized; finally, intelligent unmanned warehouses effectively use automatic three-dimensional storage, visual recognition and other technologies to achieve efficient collaboration between equipment, machines and systems.

ObjectiveTo explore the accuracy and effectiveness of infrared thermal imaging body temperature monitoring equipment in non-contact continuous body temperature monitoring, and to provide a scientific evidence for clinical application. Methods There were 30 volunteers to take part in the experiment. The body temperature of them was measured simultaneously by wireless body temperature tag and infrared thermal imaging body temperature monitoring device at the same room temperature. Data were recorded every 3min at the same room temperature and monitored for 8 hours, and the temperature values measured by the two temperature measuring devices were compared using SPSS and MedCalc software.The Bland-Altman analysis was performed using the MedCalc 19.0.7 statistical software to evaluate the consistency of the body temperature measured between the new infrared thermal imaging body temperature monitoring device and the wireless body temperature tag. Conclusion The temperature monitoring device of infrared thermal imaging is as accurate and stable as wireless body temperature tag. The temperature measurement data of clinical infrared thermal imaging temperature detection equipment is accurate and reliable, convenient, fast and safe, which is worth promoting.

In order to explore the distribution of typical soil pollutants in the retired site of the original Jema chemical plant, this paper selects the observation point to determine the typical pollutants and the spatial distribution of pollutants by the method of high-density electrical resistivity tomography (ERT) and thus analyze the typical pollutants combined with Hydrus-1d software. The results show that the typical soil pollutants are volatile organic matter, and pesticides respectively, and are mainly distributed in the water-rich area of weathered cracks. After about 600 days, the soil pollutants show an overall decline trend, and completely reach the groundwater after about 2400 days.

In this paper, an infrared thermal imager is used as a measuring instrument to build an emissivity test platform, and the system is used to measure the emissivity of defective coatings. By comparing the measured value with the true value, the effectiveness of the double temperature method and the reference volume method for the measurement of the emissivity of defective coatings is investigated. The results show that amid the use of the reference volume method, the radiation temperature of the defective coating is 317.93K, the ambient temperature is 303.07K, the emissivity of the reference coating is 0.3124, the radiation temperature of the reference coating is 311.21K, and the measurement error is not more than 0.23%; while in the use of the double temperature method, the ambient temperature is 299.15K and 300.62K, the radiation temperature of the defective coating is 307.09K and 310.22K, and the radiation temperature of the intact coating is 304.02K and 306.30K when the defective emissivity is closest to the standard value, but the error is still 9.2%.

Mobile energy storage has the advantages of flexible movement and convenient access. It provides flexible power supply according to special user load characteristics Program; and provide non-stop operation support for low-voltage load users. Take a special user of fried tea in a mountainous area as an example, verify the effectiveness of the mobile energy storage scheme by comparing the peak-valley difference, channel utilization rate and load limit with original power supply scheme and newly built power supply scheme.

Analytical solution based on the separating variable method has been accessed according to solving the paraxial beam equation in cylindric coordinates in free space. The Airy- Gaussian wave packets with complex variables are combing the Airy function with the complex variables and the Gaussian beams.

Although fundus fluorescein angiography is an imaging modality that supports ophthalmic diagnosis, it requires the intravenous injection of harmful fluorescein dye. We propose the synthesis of fluorescein angiography images from fundus structure images to avoid injection. Specifically, we automatically synthesize high-resolution fundus fluorescein angiography images through an algorithm that integrates a generative adversarial networks and image stitching and enhancement. By evaluating the peak signal-to-noise ratio and structural similarity index of the proposed algorithm, pix2pix, and cycleGAN, we confirmed the superior performance of our proposal. To further validate the proposed algorithm, we compared the fundus fluorescein angiography images synthesized by our algorithm, pix2pix, and cycleGAN. The experimental results show that our algorithm provides the highest resolution and quality in the synthesis of fluorescein angiography images from fundus structure images among the evaluated methods.

In the inter-satellite laser communication, a reliable communication link requires the boresight tracking accuracy between the optical transceivers to be sub-micro radians, and the control error caused by the vibration of the satellite platform is the most important factor affecting the optical communication link. The vibration and the effect of the adopted suppression scheme largely determine the tracking accuracy of the PAT system. Therefore, the impact of reducing the vibration on the optical communication link is a prerequisite for establishing stable satellite optical communication links. This paper uses the active compensation of the satellite platform vibration as the research direction, and proposes a composite control micro-vibration suppression algorithm based on the RBF neural network. On the basis of traditional PID control, adaptive RBF neural network feedforward control and PID control combination constitute composite control, design and establishing satellite platform vibration suppression system, simulation verifies the performance of traditional PID control and RBF composite control algorithm, result indicates that the RBF composite control algorithm has increased by 80% compared to traditional PID control.

Some criminals use cameras to steal secrets and privacy in order to make huge profits. The improper use of cameras has brought great losses to the country and the people. However, the current camera detection method based on the cat-eye effect is easily affected by the reflection of the background, resulting in false alarms and affecting the discrimination of the target. In order to improve the accuracy of cat-eye target recognition in complex backgrounds, this paper proposes a new method of cat-eye target recognition based on the fusion of dual-spectral imaging and deep learning according to the imaging characteristics of cat-eye effect echo, background and noises. The method of dual-spectral frame difference is used to filter out the background interference. Then we combine the knowledge of machine vision and deep learning to realize the cat-eye target recognition through the recognition threshold and machine discrimination. An experimental system is established in this paper. The result shows that this method can effectively suppress background interference in the recognition of close-range cat-eye targets, and has the advantages of high detection accuracy and fast recognition speed.

With the continuous development of ocean exploration technology, people put forward higher requirements for highspeed and long-distance underwater wireless communication technology. Underwater wireless optical communication (UWOC) has attracted the attention of many scholars because of its high transmission rate, large capacity, low power consumption and small size. In this paper, an underwater communication scheme using blue-green excitation (532nm) as signal source is presented from the point of view of hardware and software design. This paper establishes a model by mathematical method, analyses many factors that affect the state of underwater optical communication link, simulates the real underwater channel environment by Monte Carlo method, establishes end-to-end signal strength model, and finally simulates and verifies the communication system by MATLAB software.

At present, there are many theory analysis on the cat eye characteristics of different targets, but the experiment for cat eye characteristics measurement of dynamic sky target has not been reported. In order to validate the feasibility of the detection of the cat eye effect of the sky target through active laser, an experiment for cat eye characteristics measurement of sky target is designed and put into practice. Firstly, based on the theory analysis of the cat eye characteristics of the sky target, a scheme of the experiment for cat eye characteristics measurement is designed. Then the main technology difficulties of the experiment and correspondingly resolving methods are brought forward, and the experiment is put into practice through the flow. Finally, a cat eye characteristics index is brought forward to analyse the measurement data, which can give a suitable evaluation to the implementation of the experiment. The experiment result indicates that the detection of the cat eye effect of the sky target through active laser is feasible.

With the development of the integrated circuit manufacturing process, the critical dimension of optical lithography is reduced. Due to the optical diffraction effect, the influence of the distortion of the lithography output pattern on the integrated circuit is gradually increasing. Mask optimization in lithography is a very critical issue. In this paper, a residual network-based mask optimization method is proposed. Using the optimization masks generated by the traditional gradient descent method and its corresponding initial input masks as the training set, the residual network is trained by the inverse lithography optimization process. The parameters of the residual network weight layer are optimized. The optimized results are projected in the forward lithography model to obtain an exposure pattern of the wafer. Compared with the traditional gradient descent method, this method can improve the calculation efficiency and realize the distortion correction of the images generated by lithography.

Terahertz waves not only have the advantages of good penetration, low attenuation, strong collimation in the propagation through insulating dielectric materials, but also have high resolution in 3D tomography imaging and visualization. It has a good application prospect in the field of defect detection of electrical equipment. Polyethylene (PE) material has excellent insulating properties, which has important applications in electricity, however, various defects will occur in the process of production, transportation, and during the usage. The common testing methods have some limitations in the nondestructive testing of polyethylene materials. THz reflection imaging was performed on the simulated polyethylene defect samples, the results proved that the internal information such as the location and shape of PE samples can be detected. Meanwhile the minimum detectable defect size is determined, and the experiment showed that the defect with a diameter of 0.8 mm can be accurately resolved, which can provide theoretical and experimental basis for detecting the internal structure.

Compressive sensing is a promising theory that can sense data in a sub-Nyquist sampling. This theory has developed rapidly in many fields as soon as it appeared. It depends on the sparsity of the signal and senses the signal by low measurement and sparse reconstruction. In theory, sparse reconstruction is the core factor of compressive sensing theory and its application. In order to explore the feasibility of applying compressive imaging in remote sensing, this paper investigate the effect of sparse reconstruction on remote sensing images using typical datasets. The reconstruction algorithms such as convex optimization and greedy are introduced to implement the image reconstruction. The quality of reconstructed images is measured by PSNR index with respect to the different datasets and algorithms. The simulations show that the sparsely reconstructed remote sensing images keeps the image quality under different compression ratios of compressive imaging. The results verify the feasibility for applying compressive imaging in remote sensing.

The use of space-based surveillance systems to implement long-distance, high-precision detection and imaging of space targets is of great significance for mastering space activities. The basic principles of laser reflection tomography are introduced. For the spin-stabilized satellite target, the parameter index of the space target laser active detection system is designed, and the orbit of the imaging satellite and the target satellite are designed. The satellite is obtained by constructing a three-dimensional model of the satellite. Target multi-angle laser echo, and then use different image reconstruction algorithms to achieve satellite target laser reflection tomography, which can provide a reference for the design of laser active imaging system.

Analytical solution basing on the separating variable method has been accessed according to solving the (1+3)D Pxi-axis equations in cylindrical coordinate system. The self-decelerating Airy-Elegant-Laguerre-Gaussian wave packets are constructed by the Airy pulses in temporal domain and the Elegant-Laguerre-Gaussian wave packets in spatial domain.

Photonic generation and processing of high-frequency and large-bandwidth microwave arbitrary waveforms have become an increasingly important area that can find numerous applications, such as in ultrawide-band (UWB) communication systems, radar, and other warfare systems, and the quality directly decides the system performance. Based on the microwave photonic channelization, arbitrary waveforms were generated through dual optical frequency combs (OFCs) with different free spectrum ranges (FSR). Due to the multiple optical channels with tunable amplitude and phase, the fundamental and higher harmonics are generated simultaneously and used to synthesize into the required waveforms. Combining the advantages of low-loss broadband photonics and microwave with fine narrowband control, the proposed channelized synthesis arbitrary waveform overcomes the electronic bottleneck of ultra-wideband analog processing and opens up a whole new solution to microwave signal generation. The simulation experiment system based on Optisystem software is conducted, the results confirm that an arbitrary wave, such as triangular, square, and sawtooth will be generated by adjusting the channel parameters, and the accuracy of the generated waveforms can be improved by introducing the fifth Fourier component. Compared to the waveform synthesized by the third-order harmonic, the root mean square error (RMSE) of the fifth-order harmonic is increased by 17%-20%.

Transmission towers collapsed when facing strong tornadoes. Jiangsu province is the province which faces most tornadoes in China. In May 14^th 2021, an EF3-scale tornado attacked Shengze, Jiangsu, some 110ZGu2 drum-shaped transmission towers collapsed. The software Abaqus with beam elements was utilized to analyze the dynamic response of the tower. The simulation results are consistent with the actual failure mode, sudden change of load direction would bring the impact load to tower.

Aiming at the problem of high energy consumption of rural sewage treatment equipment, combined with the case of Qinghe Village sewage treatment project in Dawa District, Panjin City, the operation effect and process advantages of integrated solar photovoltaic power generation equipment with MBBR process as the core in practical application are analyzed. The configuration and technical characteristics of integrated equipment are introduced. Through actual operation monitoring, the main water quality index of the treated effluent can reach the level 1 B discharge standard of the Pollutant Discharge Standard of Urban Sewage Treatment Plant (GB 18918-2002). The equipment has stable operation and a low failure rate. It is suitable to be popularized and applied in rural areas because of the low efficiency and high cost of the commonly used rural domestic sewage treatment technology.

As the high-speedy development of social economy, the sustainable utilization of urban energy has attracted widespread concern. Considering the adjustment of energy sources structure, promoting energy efficiency and converting to clean energy have been established as alternative strategies. Additionally, among them the development of distributed energy in accordance with local conditions is an efficient and convenient way. While the natural gas distributed energy system reproduces electricity, steam and hot water can be supplied to the surrounding area in the meanwhile, which immensely improves energy efficiency. Solar thermal utilization is the conversion of solar radiant energy into heat or electric energy. This process can be better integrated with the natural gas distributed energy system. Accordingly, as a clean power source, solar radiant has broad development prospects.