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The 6Li(16O,19Ne*)3H multi-nucleon transfer-reaction experiment was performed to populate the highly excited states in 19Ne. The subsequent decay particles, 4He or proton from the 19Ne resonant states, were detected in coincidence with the recoil 3H. The excitation-energy spectra of 19Ne were reconstructed by using the detected proton or 4He and the deduced 18F or 15O, respectively. The broad resonance at about 7.85 MeV (1/2+) was observed with partial decay widths updating the previously reported values, which may have significant impact on the destruction of 18F in astrophysical processes. Several resonances up to very high excitation energies have been identified with large α-clustering strength, which confirm the formation of the cluster structure with one-hole configuration in light nuclei, and encourage further systematic studies of cluster structure in 19Ne.

In the harmonic power flow calculation of the power grid, the indeterminacy of new energy generation, the volatility and intermittency of nonlinear load will lead to the uncertainty of the injected harmonic current. In order to deal with the uncertainty information in the power grid, relative distance measurement (RDM) is used instead of point values to describe the uncertainty of distributed generations(DGs) output and state variables. In this paper, the RDM harmonic source model is built to solve the interval harmonic power flow. Through a typical 33-node distribution network calculation example, it is testified that the RDM Power flow algorithm has sufficient completeness and low conservatism compared with the traditional interval algorithm and Monte Carlo method.

A transfer reaction and cluster-decay experiment, C( O, Mg α+ Ne)α, was performed at a beam energy of 96 MeV. Both recoil and decay α particles were detected in coincidence, allowing us to deduce the energy-momentum of a Ne fragment. A number of resonant states of Mg were reconstructed up to an excitation energy of approximately 30 MeV. Owing to the experimentally achieved excellent resolutions of the Q-value and excitation-energy spectra, the relative decay widths for each resonant state in Mg to various final states of Ne were extracted, along with the total decay width. The obtained results provide good testing ground for theoretical descriptions of multiple clustering configurations in Mg.

In order to manage the level of power quality more effectively, a comprehensive evaluation method of power quality based on Attribute Hierarchy Model (AHM)- Criteria Importance Through Intercriteria Correlation (CRITIC) is proposed in this paper. Firstly, collect expert opinions and determine the subjective weight of each power quality index based on AHM method. Secondly, the power quality data of monitoring points are counted and processed based on CRITIC method, so as to obtain the objective weight of each index. Then, the comprehensive weight of each power quality index is determined based on the minimum discrimination information method. Finally, according to the standard grading and index comprehensive weight, the comprehensive power quality evaluation of each monitoring point is carried out. Through the analysis of practical examples, it is verified that the proposed method can comprehensively consider the subjective and objective factors and obtain more accurate and comprehensive power quality evaluation results.

This paper proposes the data mining method of voltage sag severity based on DHP algorithm and replaceable coefficient to assess the risk of voltage sag. The DHP (Direct Hashing and Pruning) is served to mine the relationship between voltage sag characteristic attribute (VSCA) in the fault scenario and the voltage sag severity (VSS) of node. Using direct hash pruning technology, frequent item sets can be found quickly and mining efficiency can be improved. The association rules are matched with the actual fault scenarios through replaceable coefficients to get the VSS of actual fault scenarios. Finally, the effectiveness and accuracy of this method are verified by simulation and examples.

In order to solve the problem of identification and verification of topological relationship between feeder and distribution transformer in distribution network, a new identification method of feeder-transformer relationship in active distribution network based on power restoration information matrix is proposed. Firstly, the identification model of feeder-transformer relationship is established through the distribution network feeder-transformer information matrix. Then, through the identification model of feeder-transformer relationship, the real-time power restoration information matrix (RRIM) and standard power restoration information matrix (SRIM) are established to describe the power restoration distribution transformer under real-time and standard conditions. Finally, the feeder-transformer relationship error information matrix is established through the difference between RRIM and SRIM to describe the name information of distribution transformer with misconnection and leakage on a feeder. The case analysis shows that this method can identify the feeder-transformer relationship of distribution network based on the topology information of DMS and real-time distribution transformer power restoration information. The method is simple and reliable, can better meet the actual needs of the site, and has good popularization value.

Image quality evaluation is a key factor in the advancement and improvement of display technology, which could lead to effective improvement through the evaluation result from various aspects to achieve the better result further. However, display principles and image characteristics should be considered for Image quality evaluation. For three-dimensional (3D) holograms, charge-coupled devices are mainly applied to capture and record reconstructed images for analysis. 3D holograms have multiple depths and thus can lead to varying light intensities at the information points of the reconstructed images during image acquisition. Finally, it will lead to poor analysis results. Aiming at the previously mentioned problem, an algorithm called three-dimensional structural similarity (3D-SSIM) is proposed in this study. It is expected to optimize hologram evaluation and analysis. A fixed-focus shooting system matching silhouette sampling and SSIM is proposed to sample objects with 360° in order to implement 3D SSIM evaluation. This study successfully optimized the hologram evaluation method, leading to more accurate image evaluation results of hologram algorithms or holographic display systems.

In this study, 45Si2MnCr2Mo steel was fabricated by casting, hot rolling, and normalizing, followed by tempering at different temperatures from 180 to 520 °C for 2 h. Special attention was paid to the effects of tempering on the microstructure and mechanical properties of the steel. The results indicate that microstructure of tempered steel consists of bainite, martensite, and retained austenite (RA), and it is not sensitive to tempering at temperatures below 320 °C. However, after tempering at temperatures of 420 and 520 °C, bainitic ferrite plates merged and their lath boundaries became vague. In turn, RA decomposed, whereas carbide particles appeared and then coarsened. With increasing tempering temperature, the volume fraction of RA achieved its peak value at 320 °C and carbon concentration within RA attained its peak value at 420 °C. The optimal balance of ultimate tensile strength of 2306 MPa and total elongation of 8.24% in the steel were achieved after being normalized at 950 °C for 0.5 h and subsequent tempering at 220 °C for 2 h. These values are found to exceed those of air-cooled and isothermal bainitic steels. Finally, the correlation between microstructure and mechanical properties of the steel under consideration was discussed.

We study the eigen-energy and eigen-function of a quantum particle acquiring the probability density-dependent effective mass (DDEM) in harmonic oscillators. Instead of discrete eigen-energies, continuous energy spectra are revealed due to the introduction of a nonlinear effective mass. Analytically, we map this problem into an infinite discrete dynamical system and obtain the stationary solutions in the weak density approximation, along with the proof on the monotonicity in the perturbed eigen-energies. Numerical results not only give agreement to the asymptotic solutions stemmed from the expansion of Hermite-Gaussian functions, but also unveil a family of peakon-like solutions without linear counterparts. As nonlinear Schrödinger wave equation has served as an important model equation in various sub-fields in physics, our proposed generalized quantum harmonic oscillator opens an unexplored area for quantum particles with nonlinear effective masses.

The current work has investigated the mechanical, electronic and optical properties of Pb-free vacancy-ordered double perovskites K2PdCl6 and K2PdBr6 by using first-principles calculations based on the framework of density functional theory (DFT). The calculated lattice constants of K2PdCl6 and K2PdBr6 are close to the experimental data. It is determined by calculating the Goldschmidt’s tolerance factors and elastic constants of K2PdCl6 and K2PdBr6 that they can be stabilized into 3D cubic crystal structures. The calculated Poisson and Pugh’s ratios indicate that K2PdCl6 is a brittle material, while K2PdBr6 exhibits ductile behavior. Both K2PdCl6 and K2PdBr6 are indirect band gap semiconductors, which show suitable band gaps of 2.151 eV and 1.368 eV for optoelectronic devices, respectively. In addition, the optical properties of K2PdCl6 and K2PdBr6 in the photon energy range of 0–6 eV further reveal the application potential of these compounds in single-junction and tandem solar cells as well as other optoelectronic devices.