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With vigorous development of the maritime trade, many intelligent algorithms have been proposed to avoid collisions due to resulting casualties and increased costs. According to the international regulations for preventing collisions at sea (COLREGs) and the self-evolution ability of the intelligent algorithm, the collision avoidance trajectory can be more consistent with the requirements of reality and maritime personnel. In this paper, the optimization of ship collision avoidance strategies is realized by both an improved multiobjective optimization algorithm NSGA-II and the ship domain under the condition of a wide sea area without any external disturbances. By balancing the safety and economy of ship collision avoidance, the avoidance angle and the time to the action point are used as the variables encoded by the algorithm, and the fuzzy ship domain is used to calculate the collision avoidance risk to achieve collision avoidance. The simulation results show that the proposed method can optimize the ship collision avoidance strategy and provide a reasonable scheme for ship navigation., 1. Introduction Collisions are one of the biggest problems in terms of safe navigation at sea. With the development of science and technology, a substantial amount of equipment has been [...]

Liner is an important component connecting brake oil pipe and brake in automobile brake system, and the oversize of inner diameter will seriously affect the brake performance of vehicles. Aiming at the problems of low efficiency, poor accuracy and inconsistent detection standards in the manual measurement of liner inner diameter, a method for measuring liner inner diameter based on machine vision was proposed. The inner diameter of liner was preprocessed and located by using bilateral filtering, improved Otsu threshold method and morphological method. An improved Canny edge detection operator was used to extract the inner diameter contour points, and the least square method was used to fit the circle based on Tukey weight function to calculate the inner diameter size. The experimental verification shows that the measurement error value of the detection algorithm is within ± 0.01 mm, the measurement accuracy is 98.9%, the missing rate is 0, and the passing rate is 1.1%, which can meet the actual measurement requirements of enterprises. [ABSTRACT FROM AUTHOR]

Metal droplet deposition is of fundamental importance in many industrial and manufacturing processes. An in‐depth understanding of the fundamental issues of metal droplet deposition is particularly crucial for developing droplet deposition‐based engineering manufacturing technologies. This review systematically introduces the evolution of metal droplet deposition stages and characteristic behaviors in terms of metal droplet deposition dynamics. The characteristic morphologies of single‐metal droplets after solidification, that is, gas entrapment, ripples, bulging edges, and splashing, are reviewed. The formation mechanisms and influencing factors of different droplet morphologies are summarized. Moreover, the deposition strategy of multiple metal droplets to promote good interfacial bonding is further concluded. Based on these theoretical foundations, three typical engineering manufacturing techniques based on metal droplet deposition, that is, thermal spraying, soldering, and droplet‐based 3D printing, are presented to elucidate further the advantages and potential of metal droplet deposition applied to engineering manufacturing. Finally, some existing problems and future research perspectives are discussed. [ABSTRACT FROM AUTHOR]

To adapt to the complex and changeable electromagnetic environment of radar detection, improve the jamming effect on frequency‐agile radar and low probability of intercept radar, and solve the problem of poor jamming effect caused by intra‐pulse jamming lagging behind target radar signal, a Convolutional Neural Network—Deep Neural Network jamming waveform generation method, based on prior global information of radar signal, is presented in this study. This proposed method uses two networks to generate the overall interference waveforms. One Convolutional Neural Network—Deep Neural Network derives prior global radar information from local prior radar information, which is used by the other Convolutional Neural Network—Deep Neural Network to generate interference. In the whole scheme, an algorithm to design the intra‐pulse interference waveform based on the prior global information of the radar signal is proposed. The algorithm can generate the interference waveform samples from the number and area of multiple false targets and the relative peak between multiple false targets and the real target area by the relevant parameters. Then, an evaluation system (Matched filter, Constant False Alarm Rate Detector, and Distance resolution etc.) is established to evaluate the global effect of the designed interference waveforms. Finally, the time‐domain Root Mean Squared Errors is used as the loss function to optimise the training of the network and ultimately achieve the requirement of generating intra‐pulse adaptive interference waveforms based on radar signal fragments. The principle of generating interference waveforms is based on various aspects of the evaluation of the interference effect, which enhances the time domain correlation between multiple false target areas, thereby boosting the interference effect on the radar. The experimental results show that the proposed method based on the Convolutional Neural Network—Deep Neural Network can effectively solve the problem of intra‐pulse interference lag and small effective interference area after the pulse pressure of the interference waveform matching filter. This study offers certain reference significance for the adaptive interference waveform design based on radar prior global information. [ABSTRACT FROM AUTHOR]

How to design the ratiometric thermometer with high sensitivity is a monumental challenge. If the sensitivity can be superposed like the stack of toy bricks, the temperature‐sensing performances will be significantly improved. To achieve sensitivity superposition, a method of dual‐wavelength (980 and 379 nm) excitation in consideration of the sensitivity of integral form is designed and the sensitivity is expected to be manipulated. Herein, compared with conventional 980 nm single excitation, the increase in Er3+ luminescence with dual‐wavelength excitation is attributed to its downshifting luminescence. Under multiple exciting methods (980, 379 nm, and dual‐wavelength excitation), temperature‐sensing behaviors based on thermally (TCL) and nonthermally (NTCL) coupled levels are investigated in the range of 213–683 K. The maximum of relative sensitivity is 2.19% K−1 (based on NTCL) with dual‐wavelength excitation, which is higher than that both with 980 nm single excitation and based on conventional TCL. These results reveal that this dual‐wavelength excitation strategy is effective to enhance sensitivity for Tm3+/Er3+‐based thermometer, which provide new insights into the design of ratiometric thermometer with high sensitivity. [ABSTRACT FROM AUTHOR]

This paper presents a 132–140 GHz power amplifier (PA) array in 0.13‐µm SiGe BiCMOS technology. The four dielectric‐loaded end‐fire antennas are integrated with the PA array on chip. With the absence of the lossy power combining networks at the output, the presented PA array achieves a measured maximal effective isotropic radiated power of 29.7 dBm. The array size is only 6.14 × 2.49 mm2 and consumes 5.16 W from a single 4 V DC supply. [ABSTRACT FROM AUTHOR]

This work investigates the possibility of doping Si and Sn solid solution components (separate/simultaneous incorporation) into Ti 3 AlC 2 to provide desired mechanical properties and tribological self-adaptability over a broad temperature range. The specimens are sintered at 1450 °C for 2 h in a vacuum environment with a pressure of 30 MPa. The phase composition, mechanical properties and tribological characteristics sliding against Al 2 O 3 counter balls over a wide temperature range from room temperature to 800 °C are investigated. The results demonstrate considerable lattice distortion together with significant solid solution strengthening effects in quinary solid solutions. The friction coefficients of the four solid solutions are discovered to be temperature-sensitive from the distinguished variation tendencies in the wide temperature range. The wear rates exhibit a comparable tendency with test temperature that the values are two orders of magnitude lower at 600−800 °C than those at RT−400 °C. The noticeably lubricant tribofilm is responsible for the decreased wear rate at elevated temperatures. The distinct tribological behaviors of the quaternary and quinary solid solutions are ascribed to the characteristics of the self-generated oxides. • A-site doping MAX solid solutions were synthesized by hot-pressing. • The Vickers hardness and strength were increased due to the lattice distortion. • The reduced wear rate at high temperatures is benefit from the tribo-film. • The distinct friction behaviors are ascribed to the features of produced oxides. [ABSTRACT FROM AUTHOR]

Dermatophytes are notorious pathogens capable of infecting various mammals skin, posing serious threats to human health and overall life quality worldwide. Artemisia argyi has been recorded and applied for over a thousand years to treat skin itching. Although it has the potential to be developed as a plant-based antifungal agent, it's antifungal activity and action mechanism of active ingredients are still unclear. The aim of this study was to investigate the chemical composition, antifungal activity against skin fungi, and potential mechanisms of Artemisia argyi essential oil (AEO). The chemical composition of AEO was analyzed by gas chromatography-mass spectrometry (GC-MS) firstly. Flat growth restraint and double half dilution tests was performed to evaluate AEO antifungal activity against Microsporum gypseum , Trichophyton mentagrophytes , and Trichophyton rubrum. And then, the physiological mechanism of AEO inhibiting dermatophytes was systematically explored through scanning electron microscopy, relative conductivity, membrane leakage, ROS content, and antioxidant enzyme activity. Finally, the main pathways were screened through transcriptome sequencing, while the related genes expression levels and enzyme activity were validated. Monoterpenes and sesquiterpenoids were the most highly representative class of AEO. AEO had powerful antifungal activity against M. gypseum , T. mentagrophytes , and T. rubrum , with minimum inhibitory concentration (MIC) values of 0.6, 1.2, and 1.2 μL/mL, respectively. Moreover, AEO can also damage the cell membrane integrity of T. mentagrophytes , resulting in cellular extravasation of intracellular substances. Transcriptome analysis revealed that the main target of AEO is to inhibit electron transfer and oxidative phosphorylation during respiration, ultimately leading to obstruction of normal ATP synthesis and energy metabolism in mitochondria. And a large amount of ROS will generate due to the incompletely catalysis of oxygen under mitochondrial complexes. Coupled with the decrease of antioxidant enzyme (SOD, POD) activity, excessive accumulation of ROS will cause serious oxidative damage to cells and eventually exhibiting antifungal activity against dermatophytes. The present study demonstrated that Artemisia argyi was a valuable source of active compounds with antifungal activity. These findings support AEO as a potential agent to inhibit dermatophytes and prevent related dermatophytoses. [Display omitted] • AEO inhibits the germination and growth of fungi and destroys membrane structure. • Oxidative phosphorylation pathway of dermatophytes is hindered after AEO treatment. • AEO induces ROS bursts and antioxidant system imbalances of dermatophytes. [ABSTRACT FROM AUTHOR]

Cholestatic liver injury (CLI) is a clinical syndrome caused by impaired bile excretion and is almost asymptomatic in early-stage. If CLI is not recognized timely, it will elicit more severe liver diseases. Therefore, earlier diagnosis of CLI is urgently needed but remains challenging. On the basis of the consensus that elevation of serum alkaline phosphatase (ALP) is the most susceptible indicator of earlier cholestatic diseases. Herein, we conjugated dicyanoisophorone with hydroxyl-substituted coumarin derivative to afford an intramolecular charge transfer (ICT)-based fluorophore TX-OH , and successfully constructed an enzyme activatable fluorescent probe TX-PS , which enables specifically detecting ALP with near-infrared emission (720 nm), large stokes shift (198 nm) and excellent linear relationship (R2 = 0.9969) between fluorescence intensity and the concentrations of ALP (0–100 U/L). Moreover, TX-PS exhibits applicable for imaging of ALP activities in living cells and zebrafish with ignorable toxicity and shows great potential to visually screen ALP inhibitors. Importantly, the liver tissues from CLI mice displayed remarkably higher fluorescence intensity than that from normal mice, suggesting the valuable capability of TX-PS for evaluating CLI degree. Overall, this work affords a powerful tool for earlier diagnosis of CLI and high-throughput screening of ALP inhibitors or new drugs for CLI therapeutics. [Display omitted] • ALP-specific activatable fluorescent probe TX-PS was constructed with near-infrared emission and large stokes shift. • TX-PS exhibits excellent performance for imaging ALP in living systems and shows great potential for drug screening. • Diagnosis of cholestatic liver injury was realized by using the ALP-specific fluorescent probe for the first time. [ABSTRACT FROM AUTHOR]