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Aroused by plant photosynthesis, Z-scheme heterostructures have been considered as a potential photocatalyst for solar-driven water splitting to solve the current energy crisis. Hence, based on first-principles calculations, we predict that Sc2CF2/Janus MoSSe can be used as a Z-scheme heterostructure for efficient photocatalytic water splitting. The research shows that the traditional type-II to direct Z-scheme heterostructure conversion can be realized through different stacking methods of Sc2CF2 and Janus MoSSe. Through the built-in electric field and band bending theory, the transition path of photogenerated carriers is analyzed, which reveals the completely different photocatalytic mechanism of type-II and direct Z-scheme heterostructure. Surprisingly, the direct Z-scheme heterostructure displays a high overpotential of the hydrogen evolution reaction ( χ H 2 =1.01 eV) and the oxygen evolution reaction ( χ O 2 =1.46 eV) compared with the type II heterostructure. More importantly, the direct Z-scheme heterostructure has an ultra-high solar-to-hydrogen (STH) efficiency (36.1%), which breaks through the limitation of traditional theoretical efficiency and reveals a tremendous prospect of commercial application. Furthermore, the calculation of free energy confirms that the water splitting reaction on the direct Z-scheme heterostructure occur spontaneously under the external potential, but not for type-II heterostructure. Finally, introducing the additional electronic conductor (N-doped graphene) can accelerate the electron (hole) transfer and interlayer carrier recombination, which will further improve the photocatalytic performance of Z-scheme heterostructure. These distinctive features make Sc2CF2/Janus MoSSe heterostructure as promising Z-scheme photocatalyst for water splitting.

Two-dimensional Janus nanomaterials, due to their unique electronic, optical, and piezoelectric characteristics resulting from the antisymmetric structures, exhibit great prospects in multifunctional energy application to alleviate the energy crisis. Monolayer Janus Pb2SSe, with a black phosphorus-like structure and an indirect band gap of 1.59 eV as well as high carrier mobility (526-2105 cm2 V-1 s-1), displays outstanding potentials in the energy conversion between nanomechanical energy, solar energy, waste heat, and electricity, which has been comprehensively studied utilizing DFT-based simulations. The research results reveal that monolayer Pb2SSe not only possesses giant in-plane piezoelectricity of d11 = 75.1 pm V-1 but also superhigh out-of-plane piezoelectric coefficients (d31 = 0.5 pm V-1 and d33 = 15.7 pm V-1). Meanwhile, by constructing Pb2SSe bilayers, the out-of-plane piezoelectric coefficients can be significantly enhanced (d31 = 19.2 pm V-1 and d33 = 194.7 pm V-1). In addition, owing to the small conduction band offset, suitable donor band gap and excellent light absorption capability in the Pb2SSe/SnSe (Pb2SSe/GeSe) heterostructure, the power conversion efficiencies were calculated to be up to 20.02% (Pb2SSe/SnSe) and 19.28% (Pb2SSe/GeSe), making it a promising candidate for solar energy collection. Furthermore, from the thermoelectric electron and phonon transport calculations, it can be found that the Pb2SSe monolayer is an n-type thermoelectric material with ultrahigh ZT = 2.19 (1.52) at room temperature, which can be traced back to its ultralow κL = 0.78 (0.99) W m-1 K-1, and superhigh PF = 10.18 (8.25) mW m-1 K-2 along the x(y) direction at the optimal doping concentration at 300 K. The abovementioned versatile characteristics in the Janus Pb2SSe monolayer, along with its comprehensive stabilities (energy, dynamic, thermal, and mechanical stabilities), highlight its potential in clean energy harvesting.

Due to the complex and changeable operating conditions of spacecraft equipment and the relatively harsh operating environment, the rate of system performance degradation and failure and the probability of failure are increased. Therefore, it is of practical significance to timely and accurately evaluate the health condition of spacecraft equipment in the early stage before serious accidents are caused, especially in the early stage when the performance of the equipment system degrades. In this paper, a new health condition degradation monitoring model called ADF-GMM for spacecraft equipment operation is proposed based on massive condition monitoring data. First, the key features that contain performance degradation information of the space equipment were selected by Augmented Dickey-Fuller (ADF) test. Then, a Gaussian mixture model (GMM) was established to describe the probability density function of the key features and a health condition monitoring index is calculated to implement the equipment condition monitoring. The proposed ADF-GMM method was applied to the Prognostics and Health Management (PHM) of momentum wheel bearing (MWB) degradation, and the feasibility and effectiveness of the proposed method were verified.

With the development of edge computing, internet of things, connected vehicles and big traffic data, future urban traffic signal control will be improved in several aspects. Future urban traffic signal control systems will be a cooperative and network system, which contains abilities of detection data sharing, real-time optimization, synchronized control, comprehensive -monitoring, fault -tolerant and coordination evaluation. With these new features and functions, urban signal control systems will be intelligent and efficient.

Treatment resistance leads to physiological, psychological, and economical effects among patients with anti-N-methyl d -aspartate receptor (anti-NMDAR) encephalitis, and the clinical and immune characteristics of these patients remain to be described. According to our clinical experience, bortezomib may be effective due to its plasma-cells depletion ability. Herein, the clinical presentations and immune parameters, including B cell and antibody secreting cell (ASC) abundance, of 5 enrolled treatment-resistant patients are described. When compared with 5 treatment-sensitive cases, the patients had serious clinical presentations but comparable B cells and ASCs. After receiving bortezomib, the ASC count and anti-NMDAR antibody titers decreased effectively. All 5 patients had a favorable prognosis (mRS ≤ 2) with a median follow-up of 31 months without severe side effects or relapse.

Considering the bright future of intelligent driving and automatic driving technology, many researchers pay attention to the significance of traffic signs detection and recognition. In this paper, a fast and accurate traffic signs detection and recognition model was proposed, which uses a detector similar to the fully convolution network and one stage method in semantic segmentation problem to localize the traffic signs in a pre-pixel fashion. Compared with other state-of-the-art object detection networks such as Faster R-CNN [1] and YOLOv3 [2], the semantic segmentation network proposed in this paper does not need predefined anchor, so it completely avoids the complex calculation and super parameter settings related to anchor boxes, which greatly reduces the workload of training and accelerates the model inference procedure.

We herein to describe the response and the potential treatment mechanism of low dose rituximab in patients with treatment-resistant chronic inflammatory demyelinating polyneuropathy (CIDP) with antibodies against neurofascin-155 (NF-155). Patients received 100 mg rituximab once weekly for 4 weeks followed by 100 mg per month for 2 additional doses. Clinical function scores, Fahn- Tolosa-Marin Tremor Rating Scale (FTMTRS) and flow cytometry of peripheral blood were scheduled before and at 1, 3, 6 months after rituximab treatment. All clinical function score including MRC, INCAT, Hughes, mRS, ODSS and FTMTRS scores showed obvious improvement at the post-treatment follow-up 1,3,6 months in comparison with baseline values. The proportion of CD19 + CD27+, CD19 + CD38+ and CD138 in lymphocytes of all patients declined at 1,3,6 month and the proportion of CD19 + CD24hiCD38hi in one patient was increased at 6 months after rituximab treatment. Low dose rituximab can significant improve disease severity and disabling tremor of CIDP patients with anti-NF155 antibody by the powerful role of B cell depletion within six months and subsequent reestablishment of B-cell subsets including increasing regulatory B cells, inhibiting memory B cells and reducing plasmablasts.

An optical sulfonamides sensor is fabricated based on a molecular imprinted resin templated by nanocrystalline cellulose. A chiral nematic imprinted composite film is synthesized which is subsequently treated with removal of templates to generate a red reflecting photonic film. The film shows a naked-eye color response to sulfanilamide, which is related to reassemble imprinted sites in the chiral nematic structure, resulting in a yellow reflecting film. Upon exposure to various antibiotics, it can be simultaneously in selectively response to three sulfonamides. This strategy facilitates enormously potential application of the resin as battery-free and portative optical monitoring sensors.

Graphene has attracted intensive attentions due to its significant optoelectronic performances. Photovoltaic effect and photo-thermoelectric effect make graphene to be a hot choice in ultra-wide spectrum band photodetection. Thinking of serious influences such as chemical pollution and mechanical damages of CVD grown and exfoliated graphene caused by transfer and exfoliation processes, the epitaxial graphene on SiC single crystal wafer shows intrinsic and better performances. Here, high quality epitaxial graphene has been successfully synthesized by thermal decomposition of Si-terminated, semi-insulating on-axis oriented 4H-SiC (0001) wafer. Photon response of the graphene has been investigated by employing a metal-graphene-metal photodetector. The largest photo-current value obtained under 780 nm laser illumination and 10 V bias voltage is up to 2.2 × 10−7 A, which is almost 30 times greater than the dark current. While under 0.05 mW/cm2 irradiance, the highest values of responsivity and EQE are 4.48 × 10−2 A/W and 8.13%, respectively. This type of fabricated graphene based photodetector has shown steady and outstanding photo detection performances.

In this study, we propose an innovative Hf2CO2/WS2 heterostructure with excellent photocatalytic performance for water splitting based on first-principles calculations. The binding energy, and ab initio molecular dynamics (AIMD) simulations exhibit this material's excellent ambient stability. Furthermore, the band structure confirms that the Hf2CO2/WS2 heterostructure possesses the intrinsic type-II semiconductor and are well satisfied with the requirements of redox energy level in water splitting reaction. Meanwhile, the charge transfer occurs from Hf2CO2 to WS2 monolayer, which further induces the separation of photogenerated carriers and prolong the lifetime of carriers. Dramatically high visible-light absorption (~6.3 × 105 cm−1) and carrier mobility (~2.2 × 103 cm2 V-1 s-1) are found, which means that the heterostructure has adequate motive force to make the photogenerated carriers separate into different monolayers quickly before recombination. Moreover, according to Gibbs free energy calculation, HER and OER can be triggered spontaneously under the driving of external potential. The results confirm that the thermodynamic feasibility of water splitting on Hf2CO2/WS2 heterostructure surface. Hence, these distinctive features endow Hf2CO2/WS2 heterostructure with the potential ability of photocatalytic water splitting, which provides a potential avenue for the future experimental project.

The problem of deposition accuracy is encountered during gas tungsten arc welding (GTAW) based additive manufacturing when wire is fed in side direction. A mathematical model was developed to calculate the wire flying distance in arc zone, according to which displacement compensation was designed to ensure the size accuracy. When arc length was 5 mm and vertical distance of wire tip to tungsten electrode was larger than 3 mm, the horizontal distance between melting wire tip and axis of tungsten electrode was 3.5 mm. The displacement compensation was verified to be effective by forming cross-angle. The model can also be used to achieve bridging transfer, which is beneficial for smooth layer appearance.

High mobility, high structural quality and large domain decoupled epitaxial graphene on SiC (000 1 ¯ ) surface has been successfully obtained by optimizing preparation processes. The etched morphology of substrate, and the structural quality and layer stacking of epitaxial graphene were investigated. The results indicate that the surface of C face of SiC substrate with regular wide steps and free of etch pits is formed by the nearly balanced hydrogen etching. The regular surface morphology of substrate is favorable to the coalescence of graphene to enlarge the domain size of graphene and the spontaneous growth to form the decoupled graphene layers. This way significantly improves the structural quality and the Hall mobility reaching up to 9075 cm2/Vs. This kind of EG will be more suitable for the use of ultrahigh frequency electronic devices.

To extend the application range of h-BN monolayer which possesses a wide bandgap (5.9 eV), constructing lateral heterostructures is proved to be a feasible and novel method. Here, considering C3B monolayer possessing an indirect narrow bandgap (0.67 eV), the lateral heterostructure is proposed by using h-BN monolayer to hybridize with C3B monolayer. The structural, electronic, optical and transport properties of the h-BN/C3B lateral heterostructures are systematically investigated by performing first-principles calculation. The calculated results demonstrate that the electronic properties of the studied lateral heterostructures can be easily modulated by strain and external electric field. Specifically, the (ABNM)2-(AC3BM)2 exhibits metal-to-semiconductor transition under different strain conditions and the bandgap of the (ABNM)2-(AC3BM)2 can be adjusted from 1.03 to 2.62 eV by applying external electric field vertically. In addition, the optical calculations reveal that (ABNM)2-(AC3BM)n behave outstanding optical-absorption capacity in visible region. Furthermore, the calculated asymmetrical carrier effective masses suggest that the migratory directions of electron and hole are parallel to the interface. These highly-tunable electronic properties and favorable optical performances of the (ABNM)2-(AC3BM)n lateral heterojunctions may facilitate their practical applications for nanoelectronics and optoelectronics.

Wire and arc additive manufacture (WAAM), as an emerging and promising technology of metal additive manufacturing, it lacks of experimental works to clarify the feature of geometrical configuration, microstructure and tensile properties, which can be used for further evaluating whether the as-deposited part can be used directly, and providing design reference for structure optimization. Taking 5A06 aluminum alloy additive manufacturing for example, in this paper, the geometric limitation and tensile property criteria are characterized using experimental method. The minimum angle and curvature radius that can be made by WAAM are 20° and 10 mm when the layer width is 7.2 mm. It shows isotropy when loading in build direction and perpendicular one. When loading in the direction of parallel and perpendicular to texture orientation, the tensile properties are anisotropic. The difference between them is 22 MPa.

In the past few years, scene text detection problem has attracted much attention and widely studied for many applications. Segmentation based methods are quite popular in this filed, it was not only for the simple post-processing procedure, but also for the ability of handle the various shape of text. In this manuscript, a method named CFPM-IDB was proposed which based on a new decoder module Consolidated Feature Pyramid Module (CFPM) and a light weight segmentation head Improved Differentiable Binarization (IDB). The CFPM module originated from Feature Pyramid Networks and achieved an idea trade-off between local details and macro semantic information. IDB module performed binarization process by threshold map and probability map. Combining them results in CFPM-IDB, which improved the performance of scene text detection, both precision and efficiency. Experimental results on two different datasets proved the promising advance in the accuracy and speed of this model.

Static strain can be detected by measuring a cross-correlation of reflection spectra from two fiber Bragg gratings (FBGs). However, the static-strain measurement resolution is limited by the dominant Gaussian noise source when using this traditional method. This paper presents a novel static-strain demodulation algorithm for FBG-based Fabry-Perot interferometers (FBG-FPs). The Hilbert transform is proposed for changing the Gaussian distribution of the two FBG-FPs’ reflection spectra, and a cross third-order cumulant is used to use the results of the Hilbert transform and get a group of noise-vanished signals which can be used to accurately calculate the wavelength difference of the two FBG-FPs. The benefit by these processes is that Gaussian noise in the spectra can be suppressed completely in theory and a higher resolution can be reached. In order to verify the precision and flexibility of this algorithm, a detailed theory model and a simulation analysis are given, and an experiment is implemented. As a result, a static-strain resolution of 0.9 nε under laboratory environment condition is achieved, showing a higher resolution than the traditional cross-correlation method.

We propose a high-resolution static-strain sensor based on a π-phase-shifted Bragg grating (π-FBG) combined with a wavelet threshold denoising algorithm. The Pound–Drever–Hall (PDH) technique based on a narrow-linewidth fiber laser is used to interrogate the sensor. A reference FBG-based Fabry–Perot interferometer (FBG-FP) is used to compensate the temperature and laser source frequency fluctuation. As the reflect spectrums of π-FBG have a higher SNR than FBG-FP, the SNR of PDH signals from FBG-FP and π-FBG is increased from 18.1 to 35.6 dB. Wavelet threshold denoising algorithm is used to further improve the SNR of the PDH signals (about 8 dB). As a result, a static-strain resolution of 1.0 ne is obtained in the laboratory test.

Static-strain can be detected by measuring a cross-correlation of two FBG-based Fabry-Perot interferometers (FBG-FPs). This letter addresses applying the wavelet transform to cross-correlation processing in noise-contaminated FBG-FP reflection spectrums for crust deformation measurement. Since the wavelet transform has a unique feature of varying time-frequency resolution, cross-correlation processing in the wavelet domain is more robust with correlated noise and window size and is less sensitive to nonstationary data. We discuss the experimental results in respect of the factors that could influence the sensor resolution. In addition, a staticstrain resolution of 1.3 n\(\varepsilon \) , higher than conventional cross-correlation method is obtained in the laboratory test by using this technique.

With the assistance of in-situ grown graphene on the wafers, semi-insulating 4H-SiC wafers were etched in aqueous KOH using photo-electrochemical method. The etching rate was estimated to be at about 50nm/min. By the cross-sectional scanning electron microscope (SEM) images, triangular structure in a similar size and aligned in the same direction was found on (1–100) face. Whereas on the (11–20) faces, pore channels along with [0001] direction exhibitedat the same time. Furthermore, the structure of 4H-SiC and epitaxial graphene on 4H-SiC (0001) face were respectively constructed with the purpose of figuring out the influence of graphene on the process of SiC etching. The electronic structures and electron density were calculated by first principle theory. When SiC was covered by graphene on the top, the intrinsic indirect wide band gap disappeared, though taking over by the single layer graphene characteristic Dirac cone at the Gama point and the linear dispersion representing buffer layer. In addition, predominately contribution at valence band maximum (VBM) and conduction band minimum (CBM) also changed by comparing the distribution of density of state (DOS).

Large-area uniform monolayer epitaxial graphene (EG) was prepared by the thermal decomposition of 4H-SiC in optimized temperature field. With the increase of substrate diameter, the radial temperature fluctuation also becomes more drastic. The convex and flat temperature fields with different growth system configurations were obtained by VR-PVT software. The EG surface morphology was characterized by atomic force microscopy (AFM). The graphene thickness uniformity was identified by Raman spectroscopy and scanning Kelvin probe microscopy (SKPM). After graphitization in convex temperature field with large axial and radial temperature gradients, the layer of graphene near the edge of the sample was about 1–2 layers thicker than that near the center. At the same time, many messy small steps splitting from big steps reduced the uniformity. By optimizing the temperature filed distribution the ratio of monolayer epitaxial graphene coverage increased from 65% to 94%. Furthermore, growth temperature dependence of the EG layer number and uniformity was investigated. The statistic results indicated that 1700°C was the most suitable growth temperature fabricating high quality and uniformity of EG.

Dogs are human's friends. In order to save more lives after a disaster, this paper gives a frame work for holographic in disaster search and rescue (SR) system, summarizes the development, application and characteristics of the conventional SR robot, put forward a kind of integration scheme of biological SR robot system along with animal (working dogs) and modern technology to achieve a tri-level (trainer, field command vehicle and superior command center) real-time and an air-ground network SR system with one or more dogs working as a guide. It will use the dog's physiological perception, flexibility and intelligence of the working dogs, providing the dogs with sensor module, wireless communication module, detachable micro-robot module, other auxiliary devices which are command on demand with the dogs' trainer.

The research method of identification of the electronic equipment's power-on characteristics based on the data of bus voltage ripple is introduced. The main purpose is to achieve the recognition of the equipment's power-on characteristics through a certain algorithm design, and provide reference for the follow-up intelligent applications of the bus-ripple-tester. Two methods are used here. One is frequency spectrum analysis based on the collected signals. Due to the differences of spectrum distribution between these equipment's signals collected before and after their power-on time, the frequency band of each equipment's characteristic distribution is different, which make it possible to achieve the purpose of identification. The other is the time-frequency analysis based on wavelet transform. According to the difference of wavelet energy of the equipment's signals collected before and after their power-on time, the equipment can be recognized.

At present, with the development of society and economy, Transmission and Distribution Project is increasing. Compared with the general construction projects, Transmission and Distribution construction project diversity, fluidity and complexity characteristics. Because of Transmission and Distribution construction project these peculiarities make the construction process safety management becomes more important. This paper introduced the characteristics of Transmission and Distribution Construction on the project, Transmission and Distribution of the current construction project safety management to analyze the problems in order to solve these problems of Transmission and Distribution Construction Project Safety Management made some practical

The fluctuation of polarization may cause wrong demodulation results in high-resolution static-strain sensing based on FBG-FP. This paper presents a polarization-insensitive demodulation algorithm using time-wavelet energy spectrum for single mode fiber (SMF) based FBG-FP sensor. This method can eliminate the influence of polarization instability effectively. Time-wavelet energy spectrum is calculated to get the energy distribution of the reflectance spectrums of FBG-FP on the timeline. The maximum value of the energy distribution is used to obtain the strain signal. In the laboratory, a high-resolution strain demodulation result without polarization controller is obtained.

The investigation of the two-phase flow measurement is important in industrial processes investigation. The research of the flow regimes identification has more significance. As a new instrument, virtual instrument combines computer resources, measurement and control hardware, data analysis and graphical user interface software together, which has a wide range of applications in practice. Neural network and LabVIEW are combined and applied in flow regimes identification, which advance the capability and the developing efficiency of the testing system. This paper introduces the software of gas-water two-phase flow regime on line identification based on LabVIEW with the method of neural networks.

Since 2008, 28 patients with congenital mitral regurgitation have undergone mitral valve repair with a modified edge-to-edge technique at our institution. The regurgitant mitral leaflet was sutured with a pledget-reinforced, horizontal mattress suture with No. 4-0 polypropylene on the ventricle side and a pledget-reinforced mattress suture with Gore-Tex sutures (W.L. Gore & Associates, Flagstaff, AZ) and Dacron pledgets (Chest, Shanghai) placed on the anterior and posterior annulus corresponding to the edge-to-edge suturing site. Early results are encouraging, but a longer follow-up is needed.

In petroleum industry, oil-water two-phase flows widely exist in production wells, and their measurements are of significance in oil well logging, transportations and etc. One of the techniques in common use in oil-water two-phase flow measurement is the differential pressure (DP) meters with a theoretic model connecting the mass flowrate of the mixture with the differential pressures generated by the throttling element installed inside the pipeline. In this work, a series of oil-water two-phase flow experiments were conducted in a horizontal pipe of 50 mm diameter and the flowrates were measured by a V-cone meter with a diameter ratio of 0.65. Available correlations of DP meters that developed from gas-water two-phase flows are adopted on the analysis of the measured data from the V-cone meter. A modified correlation is proposed based on the analysis and comparison between the available correlations. The experiments results have shown that the proposed method achieves better accuracy in oil-water two-phase flow measurement than other DP correlations.

The intelligent metering system, using the technique of phase-locked frequency multiplier to discrete the wave of student dormitory electronic signal, obtains TRMS measurement. The neural networks is applied to the wave of student dormitory electronic current to identify high-power load and computer, stopping the student from violating electric power regulations. The system has the functions of timing on and off, remote control and reading. It can also meet special requirements of electricity management for studentspsila dorm, such as overload judgment, illegal electric appliances identification, etc.

During CO 2 laser deep penetration welding, the laser-induced plasma significantly effects the process stability and efficient. In this study, the method of three-dimension synchrony high-speed photography is adopted to record the charge of plasma during laser deep penetration welding. The primary version image is in the image plane directly, the vertical view and the side view image also are in the same image plane by two optical fibers and finally three images distribute at the different area of a film. It is clear that the direction variation of laser welding plasma is acute. The reason is that the change of keyhole shape leads to the impact direction variation of the metal vapor to the plasma and it finally affects the motion direction of the laser-induced plasma. The plasma is in the state of irregular rotation and wobbling in space during the laser welding process. The area change curve on continuous 80 frames image are given out. The change extent of relative area on the three images are calculated and the curves of the relative area are showed. It is found that the shape of plasma change quickly and the maximum relative area ratio of the side view image is up to 40 during laser welding.

In this study, the method of three-dimension reconstruction of laser welding plasma on the basis of three-dimension synchrony high-speed photo is proposed. The method of anti-RADON transformation is used to finish three-dimension reconstruction. The anti-RADON transformation utilizes the projected data to reconstruct the initial image, which bases on the projection of the parallel beam. It is found that there are the cavitations on most section images and the area of cavitations is ever-changing. The space shape of plasma represents irregularity on the different surface.

In petroleum industry, oil-water two-phase flow widely exists in production wells, and the measurement of oil-water flow is significant in oil well logging. One method in common use is to build a theoretic model to connect differential pressures generated by a throttling set with flow-rate. Several measuring models were adopted and compared for model selection and modification. A V-cone with 0.65 diameter ratio was selected as the throttling set because of its special structure and intrinsic advantages. In the experiments, the differential pressures measured under different flow range were processed with a homogeneous flow model. And the results show that the error is small in the condition where the oil and water are well mixed, while the error is big when they are not well mixed. A polynomial of the error and the water percentage was fitted to improve the model accuracy and widen the measurement range.