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Let $\mu$ be a positive Borel measure on the interval $[0,1)$. For $\gamma>0$, the Hankel matrix $\mathcal{H}_{\mu,\gamma}=(\mu_{n,k})_{n,k\geq0}$ with entries $\mu_{n,k}=\mu_{n+k}$, where $\mu_{n+k}=\int_{0}^{\infty}t^{n+k}d\mu(t)$. formally induces the operator $$\mathcal{H}_{\mu,\gamma}=\sum_{n=0}^{\infty}\left(\sum_{k=0}^{\infty}\mu_{n,k}a_k\right)\frac{\Gamma(n+\gamma)}{n!\Gamma(\gamma)}z^n,$$ on the space of all analytic functions $f(z)=\sum_{k=0}^{\infty}{a_k}{z^k}$ in the unit disc $\mathbb{D}$. Following ideas from \cite{author3} and \cite{author4}, in this paper, for $0\leq\alpha, Comment: 7 pages

Background: The study of kerosene fuel for gasoline engines is of great significance to the supply, management, storage and transportation of military fuel, as well as its safety. Small aviation two-stroke kerosene engine fuel injection controller is the key technology of kerosene engines. It is very important to improve the performance of kerosene engine by controlling the air-fuel ratio accurately. Objective: The initial injection pulse spectrum was firstly obtained by numerical calculation in the absence of kerosene injection pulse spectrum, and then the injection controller was designed based on the initial injection pulse spectrum. Methodology: Firstly, a numerical model of the whole engine was established by using BOOST software. The air mass flow data of the inlet was obtained through numerical calculation. The amount of initial engine fuel injection was calculated according to the requirements of air-fuel ratios in each working condition, from which an initial injection pulse spectrum was obtained. Then, based on Free scale 16-bit embedded micro-controller MC9S12DP512, a kerosene engine fuel injection controller was developed, together with the circuit was also designed. According to the initial fuel injection pulse spectrum, a two-dimensional interpolation algorithm was developed by using assembly language and C language mixed programming, and the anti-electromagnetic interference ability of the controller was further enhanced. Finally, the accuracy of the initial injection pulse spectrum and the performance and reliability of the injection controller of the kerosene engine were verified by the kerosene engine bench test. Conclusion: The experimental results show that the numerical model was accurate, and the development time of the injection controller was shortened by using the numerical model to calculate the initial injection pulse spectra. The developed controller was stable and reliable, which can meet the control requirement.

Let $\mu$ be a positive Borel measure on the interval $[0,1)$. The Hankel matrix $\mathcal{H}_{\mu}=(\mu_{n,k})_{n,k\geq0}$ with entries $\mu_{n,k}=\mu_{n+k}$, where $\mu_n=\int_{[0,1)}t^{n}d\mu(t)$. For $f(z)=\sum_{n=0}^{\infty}a_nz^n$ is an analytic function in $\mathbb{D}$, the Hilbert operator is defined by $$\mathcal{H}_{\mu}(f)(z)=\sum_{n=0}^{\infty}\Bigg(\sum_{k=0}^{\infty}\mu_{n,k}a_k\Bigg)z^n, \quad z\in \mathbb{D}.$$ The Derivative-Hilbert operator is defined as $$\mathcal{DH}_{\mu}(f)(z)=\sum_{n=0}^{\infty}\Bigg(\sum_{k=0}^{\infty}\mu_{n,k}a_k\Bigg)(n+1)z^n, \quad z\in \mathbb{D}.$$ In this paper, we determine the range of the Hilbert operator and Derivative-Hilbert operator acting on $H^{\infty}$., Comment: 10pages

Temporal convolutions have been the paradigm of choice in action segmentation, which enhances long-term receptive fields by increasing convolution layers. However, high layers cause the loss of local information necessary for frame recognition. To solve the above problem, a novel encoder-decoder structure is proposed in this paper, called Cross-Enhancement Transformer. Our approach can be effective learning of temporal structure representation with interactive self-attention mechanism. Concatenated each layer convolutional feature maps in encoder with a set of features in decoder produced via self-attention. Therefore, local and global information are used in a series of frame actions simultaneously. In addition, a new loss function is proposed to enhance the training process that penalizes over-segmentation errors. Experiments show that our framework performs state-of-the-art on three challenging datasets: 50Salads, Georgia Tech Egocentric Activities and the Breakfast dataset.

Background: Garlic is one of the main economic crops in China and the planting area is increasing quickly. But the harvest process of the garlic mainly relies on manual digging, resulting in low harvest efficiency and high cost. Objective: In order to improve the efficiency of garlic harvest, and achieve the mechanization of garlic harvest. The study presents a new design of a garlic harvesting machine that can perform automatic processing and deal with the issue of garlic harvesting. Methods: Firstly, the three-dimensional model of the whole machine and the key mechanism is established and the parameters of the system are calculated by theoretical calculation. Then, the simulation be made and the design be optimized. Finally, the design was processed into a product. It employs an isolation mechanism and positioned cutting mechanism to isolate garlic and crop stubbles and keep the length of the remaining garlic straw consistent. Results: The results of field harvest experiments show that the miss digging rate, miss cutting rate and injury rate of the harvester are as low as 1.23%, 3.13% and 0.68% respectively, and the harvest efficiency is 0.06km2/h. Conclusion: The advantages of the harvester such as high harvesting rate, low damage rate, strong adaptability and high versatility, effectively improve the working efficiency, reduce the labor intensity and the harvest cost.

The normal vectors of the free-form surface profile curve are generally not in the same plane, even if the profile curve is generated from the interaction between a plane and a surface. If the 2D compensation vector is adopted to reduce the cosine error, the accuracy is limited because the normal direction of the curve plane is not considered. In this paper, a novel radius compensation method adopts the 3D compensation vector instead of the 2D compensation vector like most existing works. An approximating method is proposed to estimate the 3D compensation vector, which is composed of two parts. One is the projection of the 3D vector in the curve plane that is calculated by the normal vector of the non-uniform rational Bezier spline fit curve. The other is the normal vector of the curve plane passing the measuring point. In addition, the deviation between the workpiece and CAD model may degrade the accuracy of the radius compensation. Through theoretical analysis, the influence of the deviation cannot be ignored when the deviation is larger than 0.2 mm. By setting up this threshold, under various levels of torsion angles and deviations for the free-form surface, the results show that the compensation accuracy of the proposed method has a better performance than traditional 2D compensation methods, which decreases the maximum error from 70.8 to 2.6 μm.

Among all the non-contact measurement devices, the spot laser probe achieves a good balance between accuracy and efficiency. When the laser probe is applied to three-dimensional (3-D) measurement, the laser beam direction is essential to transform the probe indication from 1-D distance information into a 3-D vector representing differences in space coordinates. In this article, a calibration method is proposed for the laser probe mounted on the coordinate measuring machine (CMM). During the calibration procedure, the CMM moves along the user-planned path and hundreds of points are scanned in a few seconds. In order to get an accurate laser beam direction estimate, we refine the original inaccurate direction, which is specified by the mechanical structure of the probe fixture, by mapping the scanned points into a sphere. The simulation and experiment manifest that the proposed method is superior to the existing methods and meets the requirement of the micron-level measurement.

The graphene oxide (GO) and modified carbon nanotubes (MCNTs) were dispersed in water and mixed with toluene to form homogeneous emulsion, then the porous graphene–carbon nanotubes composites (MCG) were prepared through hydrothermal reaction. The adsorption mechanism of MCG was investigated by adsorption methylene blue. The morphology of MCG was analyzed by scanning electron microscope and transmission electron microscopy. It was found that MCG had rich micropore structures and MCNTs were interlaced on graphene sheets. The pore size of MCG can be effectively controlled by changing the volume ratio of toluene to the GO/MCNTs solution in the emulsion. MCG was characterized by X-ray diffractometer, Raman spectrometer, X ray photoelectric instrument and other analytical instruments. It was found that MCG had more oxygen functional groups. The experimental results show that kinetics can be well-described by pseudo-second-order model. The smaller the pore size, the higher the equilibrium adsorption capacity and the slower the adsorption rate. The adsorption thermodynamic parameters show that the adsorption process is spontaneous and belongs to physical adsorption, and high temperature is beneficial to adsorption. The fitting results of MCG-5 equilibrium adsorption data are matched with the Langmuir model and the saturated adsorption capacity is 232 mg g−1. After five cycles of adsorption–desorption operation, the adsorption capacity of MCG-5 decreases slightly.

As growing e-GaSe single crystal, volatile component and curving solidification interface spoil the qualities of crystals. The GaSe single crystal in φ19 mm×65 mm size was grown by modified vertical Bridgman method. The crystallinity and optical properties of as-grown crystals were measured by XRD and transmission spectra, respectively. The FT-IR meas- urements indicated wide transparency over the spectral range (0.65-16 μm) and low absorption coefficient (

The study of the linear and nonlinear optical properties of ZnGeP2 based on density functional theory has been carried out. In order to get a more physical picture in the infrared region, terms which are considered as the phonon effect were added to the calculated refractive dispersion curves. The phonon-corrected calculation curves show excellent agreement with experimental refractive indexes, which gives a better comprehension of the linear optical proprieties in the transparent region. The static nonlinear optical susceptibility was investigated using approaches based on the "sum over states" and the 2n + 1 theorem methods. Both of the results of these two methods reasonably coincided with the experimental results.

The optimized crystal structure, electronic structure and optical properties of Na2Ge2Se5, an excellent nonlinear crystal, are investigated by using pseudo-potential plane-wave method based on the first principles. The band structure, density of states, bond population, dielectric function, reflection spectrum, absorption spectrum, and codex refractive index of optimized structure of Na2Ge2Se5 are calculated. The results indicate that Na2Ge2Se5 is indirect wide-band semiconductor. The electronic transitions are mainly composed of Ge-4s, Ge-4p, Se-4s and Se-4p. The optical properties are determined by the interaction between Ge and Se, while Na contributes little. The reflectance spectrum and absorption spectrum indicate that there is strong absorption to ultraviolet radiation and static refractive index is 2.133. Na2Ge2Se5 possesses moderate birefringence. The results indicate that Na2Ge2Se5 is a good candidate for the optical crystals in the infrared region.