This article develops a new platoon control strategy for heterogeneous connected vehicles (CVs) subject to time delays and external disturbances. Specifically, based on the third-order vehicle model, novel controller is developed by embedding variable headway (VTH) spacing policy nonlinear motion coupling interactions between CVs. Simultaneously, an integral sliding mode (ISM) resist Then, condition of asymptotic stability CV upper bound communication delay are deduced using Lyapunov...

Abstract The accurate estimation of road friction coefficient in the active safety control system has become increasingly prominent. Most previous studies on have only used vehicle longitudinal or lateral dynamics and often ignored load transfer, which tends to cause inaccurate actual coefficient. A novel method considering transfer front rear axles is proposed estimate based braking dynamic model two-wheeled vehicle. Sliding mode technique build ideal torque controller, target wheel slip...

The diversity in floral coloration results from a complex reproductive system, which has evolved response to multiple pollinators and is intricately linked the development of pollination mechanisms. To investigate how trait variations influence reproduction Paeonia delavayi , we conducted experiments, observed insect visitation, measured traits, estimated petal anther colors as perceived by analyzed scent for two morphs (red yellow) at distinct sites. P. depended on seed production. Multiple...

We have demonstrated a helical long-period grating (HLPG) manufactured from multicore fiber (MCF) combined with twist and CO2-laser heating technology. The MCF we used behaves as kind of single mode fiber. nineteen cores are distributed hexagonally which make the structure only exist in core area after twisting. There several strong couplings between cladding modes at different wavelengths when pitch was 900 µm. extinction ratio main coupling reached 20 dB 1550 nm. investigated sensor...

Withthe advent of the 5G era, demand for data communication is increasing explosively. Extending L-band gain bandwidth considered to be most direct and effective approach capacity. However, signal excited state absorption (SESA) prevents from extending longer wavelength. In this report, Er <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> Ce are introduced into phosphosilicate fiber regulate SESA. The results show that addition Ce3+ can...

A low-numerical aperture (NA) confined-doped long-tapered (LCT) Yb-doped fiber is proposed and fabricated by modified chemical vapor deposition combined with solution doping technique. The LCT owns the core NA of ∼0.05 gain dopant diameter ratio ∼77%, a core/cladding 25/400 µm at both ends 37.5/600 in middle. laser performance demonstrated bidirectional pumping all-fiber amplifier, which 4.18-kW single-mode (M2 factor ∼1.3) output achieved slope efficiency ∼82.8%. Compared conventional...

In this work, a record output power of 4.6 kW linearly polarized and narrow-linewidth fiber amplifier based on an optimized oscillator laser (FOL) seed was realized by employing homemade polarization-maintaining Yb-doped (PMYDF), corresponding to slope efficiency 79.5% 3 dB linewidth 0.3452 nm. Through effective strategy relying decreasing the transmission length from 200 m 120 adding chirped tilted Bragg grating (CTFBG), stimulated Raman scattering (SRS) effects were well-suppressed. By...

With impedance elimination principle and phase sensitive demodulation (PSD) technique, this work aims to develop a new contactless sensor, which is suitable for the void fraction measurement of gas–liquid two-phase flow. The used overcome unfavorable influences coupling capacitances, i.e. capacitive reactances capacitances are eliminated by inductive reactance an introduced inductor. PSD technique implement measurement. Unlike conventional conductance/impedance sensors use equivalent...

Aiming at the issue of active obstacle avoidance control for intelligent vehicles under emergency, an safety collaborative system integrated with adaptive cruise (ACC), rear steering (RSC), and rollover braking (RBC) is developed. The proposed novel architecture consists a supervisor, upper controller, lower controller. supervisor decides which mode to be used based on multi-sensors information driving vehicle. Active wheel lateral acceleration feedback strategies fuzzy PID are added into...

Autonomous obstacle avoidance and decision-making algorithms for intelligent connected vehicles in a complicated transportation environment are important studies on driving. However, it is difficult to adapt more traffic based safety distance conventional potential field. Therefore, this paper, driving risk field model theory proposed involving factors vehicle conditions. A hidden Markov was used evaluate determine the motion state of surrounding vehicles. safe, feasible, smooth...

Abstract This paper develops a novel integrated collision avoidance strategy for autonomous vehicles in an emergency based on steering and braking. Specifically, the framework of is composed two parts: up-level decision-making layer low-level controller layer. The purpose to select appropriate control vehicle information, drive according instructions generated by up-level. More concretely, proposed integrating four-wheel steering, active rear differential braking with guaranteed...

A confined-doped fiber was fabricated by a modified chemical vapor deposition (MCVD) process based on refractive index matching technology. With theory and experiments, we compared the normal-doped fiber. We found that with core of 35 μm 0.07 numerical aperture could achieve single-mode output improve beam quality from 2.8 to 1.5 in laser. Meanwhile, it still possesses high laser efficiency has good stability increase pump power. It suggests MCVD may be key material for high-power excellent quality.

Machine learning (ML) methods were developed and optimized for description understanding a physical separation process. Indeed, this work indicates application of machine technique real system optimization process parameters to achieve the target. A bunch datasets extracted from resources adsorption in removal impurities water as case study test model. The is which has extensive science engineering. method was developed, order get best simulation's performance data are used correlate...

Instant messaging is an application that enables networked users to send and receive short messages. Presence provides information about users' reachability willingness accept/reject a brief chat session. Various proprietary IM presence (IM&P) solutions are currently on the market, standards emerging. There interoperability problems between two dominant (SIMPLE XMPP); as result, this important finding difficulty in widespread deployment within college campuses businesses. We describe history...

We report a novel center-sunken and cladding-trenched Yb-doped fiber, which was fabricated by modified chemical vapor deposition process with solution-doping technique. The simulation results showed that the fiber core diameter of 40 µm numerical aperture 0.043 has 1217 µm2 effective mode area at 1080 nm. It is also disclosed leakage loss can be reduced lower than 0.01 dB/m for LP01 mode, while over 80 LP11 optimizing bending radius as 14 cm. A 456 W laser output observed in MOPA structure....

Spatial division multiplexing (SDM) is one of the most important technologies that may help to solve future capacity crisis. However, date, SDM optical amplification still a challenge for its application. Herein, we numerically and experimentally demonstrated few-mode Er/Yb co-doped fiber amplifier (FM-EYDFA) extended L-band operation. A double cladding was fabricated expand bandwidth novel, best our knowledge, cladding-pumped pseudo-two-stage configuration proposed enhance gain. With an...

We demonstrate the almost complete 2 µm laser power recovery of gamma-ray-irradiated thulium (Tm)-doped silica fiber under deuterium loading. The optical–optical slope efficiency and cladding absorption spectra Tm-doped with gamma-ray irradiation treatment have been measured for comparison. It was found that irradiated could be recovered to 96.1% pristine after bleaching, which significantly degraded from 60.7% 25.3% irradiation. Meanwhile, additional attenuation D2 completely vanished....

This work focuses on the hardware improvement of a CCERT system. An inductor module is developed by simulated technique. With inductive reactance module, capacitive coupling capacitances eliminated impedance elimination principle and unfavorable influences are overcome. The digital phase-sensitive demodulation technique introduced to obtain total gas–liquid two-phase flow, including real part, imaginary part amplitude. Finally, new system prototype developed. Impedance measurement...