Since the optical signal is attenuated when it propagates forward, uncertainty of measurement at end fiber increased, which restricts performance Raman Scattering Distributed Temperature Sensing System (RDTS). Therefore, essential to study denoising method system. Existing methods, such as wavelet transform, median filtering, singular value decomposition, 1DDCNN, etc., still have room for improvement in parameter adjustment, computational complexity, and effect. Thus, we proposed a novel...

Laser micro-thrust technology is a type of propulsion that uses laser beam to ablate propellant such as metal or plastic. The ablated material expelled out the back spacecraft, generating thrust. has advantages high control precision, thrust–power ratios, and excellent performances, it played an important role in field micro-propulsion. In this study, solid micro-thruster was developed then applied for attitude satellites during on-orbit tests. had volume 0.5 U, weight 440 g, thrust range 10...

Motor rotor magnetic bridges operate under multiple physical field loads, such as electromagnetic force, temperature, and centrifugal force. These loads can cause fatigue aging failure of the bridges, especially when is operating continuously at high speeds temperatures. Therefore, analysis accelerated test cycle development a major aspect their reliability evaluation. This paper studies multi-physics load transfer characteristics establishes bridge model. A simulation conducted from field,...

We present a novel structure of planar waveguide for Yb:YAG laser amplifiers as symmetrical corner-pumped waveguide, allowing large absorption length. optimize the parameters using an amplification model. Performance including thermal effects 10-kW amplifier is simulated, demonstrating that pump efficiency and uniformity are much better than end-pumped ones. Moreover, good beam quality causing by less distortion can be expected. The power scaled from 200W to 7000W with 98.2%, leading...

The combined pulse laser (CPL) based on long-pulsed lasers has been proven to be an effective way of improving processing efficiency by combining their advantages. In this Letter, a CPL with 500 mJ millisecond and 150 nanosecond is utilized study the interaction process between silicon. Based high-speed images plasma distribution supported detonation wave (LSDW), as well height characteristics ablation morphology, energy coupling variable delay time analyzed. irradiation material within...

Cascaded mid-infrared (MIR) pulsed laser output in Er:YAG crystals at room temperature is achieved experimentally. The existence of a cascade confirmed. Furthermore, the effect on MIR performance studied. With assistance cascade, thresholds are reduced by 13.3% and 12.5%, slope efficiencies increased 3.2% 12.3% compared to non-cascade configuration 10 15 at.% Er:YAG, respectively. excited-state absorption considered be mechanism responsible for optimization. This Letter should helpful...

This paper discusses the effect of considering manufacturing tolerance uncertainty on robustness radial electromagnetic force in permanent magnet synchronous machines(PMSMs). research presents a method for robust design based Non-dominated Sorting Genetic Algorithm-II(NSGA-II). A noise table tolerances variables machine is designed to simulate performance differences caused by actual tolerances. can extract standard deviation same control scheme. In this paper, it applied 54-slot/6-pole...

Abstract Plasma ignition technology is the research frontier in field of energy and power. In this paper, a novel type plasma jet igniter called pre-combustion designed experimental results show that it has great potential strengthening stiffness, improving energy, decreasing consumption reducing ablation. The value S stiffness defined for first time to reflect characteristics jet. And effects gas flow rate, fuel-air ratio input current on are investigated experimentally. significantly...

Room-temperature cascaded mid-infrared (MIR) pulsed laser output in Er:YAG crystal is reported. The 1469nm characteristic wavelength of the cascade emission observed. excited-state absorption (ESA) determined as 1676nm. An with concentration 10at.% adopted to compare energy and non-cascaded configuration. maximum single pulse MIR increases from 1.04mJ (non-cascade) 1.51mJ (cascade), corresponding a ratio 45.2%. "cyclic cascade" considered be mechanism responsible for performance...

We present a novel structure of planar waveguide for Yb:YAG laser amplifiers allowing large absorption length. The parameters the were optimized using an 3D amplification model. performance amplifier was simulated, and comparison between cases with without considering pump saturation carried out. simulated results show that high efficiency optical-to-optical can be expected in addition to good uniformity. seeder power is scaled from 200W 7000W, corresponding efficiencies are 98.6% 68%,...

The performance of a novel, to the best our knowledge, high-power Yb:YAG planar waveguide amplifier under thermal steady-state is studied numerically. We present 3D amplification model, which considers effects temperature on Boltzmann occupation factors, pump absorption, and laser emission cross sections, in addition reabsorption saturation Yb:YAG. multipass-pumped was simulated considering loss claddings, comparison with results ideal state carried out. Our analysis show that core's rise...

Room-temperature cascaded mid-infrared (MIR) pulsed laser output in Er:YAG crystal is reported. The 1469nm characteristic wavelength of the cascade emission observed. excited-state absorption (ESA) determined as 1676nm. An with concentration 10at.% adopted to compare energy and non-cascaded configuration. maximum single pulse MIR increases from 1.04mJ (non-cascade) 1.51mJ (cascade), corresponding a ratio 45.2%. "cyclic cascade" considered be mechanism responsible for performance...

We present a novel structure of planar waveguide for Yb:YAG laser amplifiers allowing large absorption length. The parameters the were optimized using an 3D amplification model. performance amplifier was simulated, and comparison between cases with without considering pump saturation carried out. simulated results show that high efficiency optical-to-optical can be expected in addition to good uniformity. seeder power is scaled from 200W 7000W, corresponding efficiencies are 98.6% 68%,...

The laser ablation micro thruster uses the target vapor or plasma jet generated by working fluid to obtain reaction impulse and thrust. mode of is divided into two types, reflection type transmission type. In this paper, influence treatment on bonding force between layer transparent studied in mode, different kinds substrate materials mechanical properties studied. results show that surface activity PET greatly improved formation N-C=O C=O active groups after treatment, interlayer band...

The laser electromagnetic hybrid propulsion is a method that generates thrust through the synergistic action of ablation and propulsion. Laser complement each other to produce better performance. In this paper, emission spectra pulsed (PEP) assisted (LAPEP) are studied, composition, temperature density plasma plume calculated. evolution plumes combined (LEHP) in initial stage formation discharge chamber studied by using high speed camera. results show charged particles PEP LAPEP mainly C+,...