A rapid detection method for the surface defects of mosaic ceramic tiles

Due to its unique artistic value, mosaic ceramics are widely used in construction-related fields. To meet the artist's demand for high-quality mosaic ceramic to create artistic works, it is necessary to meet the needs for efficient screening of mosaic ceramic tiles. Different from the ordinary large-target ceramics, mosaic ceramics exhibit characteristics of small tile sizes, a variety of colors, large demand for quantities, and easy reflection on the surface. Common manual detection methods show problems of low efficiency or accuracy, easy to fatigue, and many others. To solve these problems, this paper proposes a new detection method to identify surface defects of mosaic ceramic tiles and designs a detection system platform to achieve rapid detection. The experiment proves that the detection system has a detection rate of 93.99% for small defects on the surface of mosaic ceramic tiles, and the detection time of a single mosaic ceramic tile is less than 0.06 s. The detection method can quickly and accurately screen out high-quality, defect-free mosaic ceramic tiles, which can effectively improve the quality and artistic value of mosaic ceramic art creation.     

Effects of preparation conditions on the morphology and performance of palladium nanostructures

Three-dimensional palladium nanoflowers (PdNF) composed of ultrathin Pd nanosheets had been synthesized by a solvothermal approach in our previous work. Here, the effects of preparation conditions on the morphology and electrochemical performance of palladium nanostructures were investigated. The explored conditions are as follows: the ratio of reducing agent to capping agent, the concentration of PdCl₂ precursor, the amount of HCl (used for PdCl₂ dissolution), the reaction temperature and time. Only when these conditions are strictly controlled, the obtained Pd material displays a uniformly nanoflower-like morphology, otherwise the Pd samples with nanoparticles or incomplete flowers can only be obtained. Then, the relationship between the morphology of Pd and its electrocatalytic activity was further studied. The results indicate that the Pd with perfect nanoflowers morphology possesses superior activity for formic acid electro-oxidation, while the Pd with incomplete flowers and ordinary (or irregular) particle morphology shows moderate and inferior activity. Therefore, the morphology-dependent electrocatalytic activity has been demonstrated in this work.     

An energy matching method for battery electric vehicle and hydrogen fuel cell vehicle based on source energy consumption rate

The smart cities development requires reducing energy consumption and using as much renewable energy as possible, so the widespread use of new energy vehicles is a very important measure. In this work, for the energy system configuration and energy efficiency balance of new energy vehicles, we propose an energy matching method to study its energy efficiency from the view point for energy life cycle. Nowadays, new energy vehicles mainly include battery electric vehicles (BEV) and hydrogen fuel cell vehicles (HFCEV). Firstly, we proposed the Source to Range (STR) model. Then, based on STR model, we used energy efficiency analysis chart to visually represent the conversion, delivery and consumption of the vehicle energy life cycle. Furthermore, we proposed a Source Energy Consumption Rate (SECR), which is used to evaluate the vehicles energy efficiency. Finally, based on STR model, we obtained the dividing line of the same SECR for new energy vehicles and equivalent fuel vehicles, which provides constraints on the vehicle energy system design. The results show that STR model can provide an effective tool for energy matching and energy efficiency analysis of new energy vehicles, and has a reference for product development of new energy vehicles.     

Microstructure and Properties of Micro-Alloyed Mg-2.0Nd-0.2Sr by Heat Treatment and Extrusion

Magnesium (Mg) and its alloys have broad application prospects in the fields such as biomedical materials and automobile manufacturing. A micro-alloyed Mg-2.0Nd-0.2Sr (wt.%) magnesium alloy is designed and obtained through semicontinuous casting. The evolution of microstructures and tensile properties are investigated with different heat treatments and extrusion treatments. The grain sizes decrease significantly after extrusion, thus changing the fracture mode during the tensile testing process. The ultimate tensile strength (UTS), yield strength (YS) and elongation (EL) of the properly processed extrusion alloy (referred to as MNS-E2) reach to 247 MPa, 228 MPa and 24%, respectively. The dramatical improvement of mechanical properties results from the refined grains and interactions between dislocations and precipitates. Some nanoparticle bands blocking the slippage and movement of dislocations are also found in the MNS-E2 alloy. The above causes combined result in an integrated effect of grain boundary strengthening, dislocation strengthening, precipitation strengthening and nanoparticle band strengthening. The contribution of strengthening mechanisms of MNS-E2 alloy consists of grain boundary with around 96 MPa, dislocations with around 3.4 MPa, precipitation strengthening with around 45 MPa and the nanoparticle band with around 18 MPa, respectively.     

Nonlinear dynamic behaviors and control based on simulation of high-purity heat integrated air separation column

In this paper, the dynamic behaviors on the basis of simulation for high-purity heat integrated air separation column (HIASC) are studied. A nonlinear generic model control (GMC) scheme is proposed based on the nonlinear behavior analyses of a HIASC process, and an adaptive generic model control (AGMC) scheme is further presented to correct the model parameters online. Related internal model control (IMC) scheme and multi-loop PID (M-PID) scheme are also developed as the comparative base. The comparative researches are carried out among these linear and nonlinear control schemes in detail. The simulation research results show that the proposed AGMC schemes present advantages in both servo control and regulatory control for the high-purity HIASC.     

An intelligent θ-Modified Bat Algorithm to solve the non-convex economic dispatch problem considering practical constraints

This paper proposes a practical formulation for the non-convex economic dispatch problem to consider multi-fuel options, ramp rate limits, valve loading effect, prohibited operating zones and spinning reserve. A new optimization algorithm based on the θ-bat algorithm (θ-BA) is suggested to solve the problem. The θ-BA converts the Cartesian search space into the polar coordinates such that more search ability would be achieved. According to the complex, nonlinear, and constrained nature of the problem, a new self-adaptive modification method is proposed. The proposed modified θ-BA (θ-MBA) is constructed based on the roulette wheel mechanism to effectively increase the convergence of the algorithm. The high ability and satisfying performance of the proposed optimization method is examined on IEEE 15-unit, 40-unit and 100-unit test systems.     

Power harmonics analysis of programmable AC power source via variation semi-sinusoidal window

Harmonic contents are employed for indicating the quality of the programmable AC power source (PACPS). However, spectrum leakage usually occurs. This paper employs a variation semi-sinusoidal window (VSSW) for performing the power harmonic analysis. Since the rolloff of the sidelobes of the VSSW is fast, experimental results show that the VSSW outperforms existing windows.     

A new method for estimating the isothermal devitrification and crystallization of mold powder slags from non-isothermal DSC data

The rate of formation of crystalline phases from liquid and glassy mold powder slags is of foremost importance in the performance of molds used for continuous casting of steel. This study shows how the Induction Period (of Šimon and Kolman) and the Kissinger methods can be combined in a kinetic model to evaluate the isothermal rate of formation of crystalline phases from thermo-analytical data – onset temperature, T_i, peak maximum temperature, T_m, shape index, S, and conversion at peak maximum, x_m – collected at various linear heating and cooling rates. The diagram of the extent of isothermal transformation as a function of time calculated for a commercial mold powder, used for casting low carbon steels, shows good agreement with the degree of transformation observed in photomicrographs of glass disks devitrified isothermally, at several temperatures for different times. Additionally, qualitative and quantitative X-ray diffraction results obtained at room-temperature from glass powder samples treated isothermally and quenched also show good accord with the degree of transformation predicted with the kinetic model developed in this work.