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Given that the conventional blockchain model for the fruit and vegetable supply chain has the problems of insufficient depth of traceability information, insufficient data correlation, and low query efficiency, a graph blockchain model was proposed in this study. Firstly, the graph theory was used to improve the block data structure of the traditional blockchain and change the storage structure of the sequence table in the traditional blockchain structure into a graph structure that can facilitate the storage of in-depth traceability information for associated storage of deep traceability information. Then, the mapping relationship between physical block data and graph block chain model was established through a graph block chain mapping model, and according to the logical structure of the fruit and vegetable supply chain, the graph block data structure was established. Customized design of smart contracts for graph blockchain data storage, query and authority management was performed to ensure the reliability of supply chain data. Finally, the graph blockchain model was developed based on the XuperChain platform and its performance was experimentally compared with that of the traditional blockchain. The results showed that the graph blockchain allows deep traceability of the fruit and vegetable supply chain and greatly improves the efficiency of data query, which can provide a new method and idea for the traceability information storage and fast query of the fruit and vegetable supply chain based on blockchain.

Hydraulic fracturing is an effective technology used to stimulate hydrocarbon production from unconventional reservoirs. Numerical simulation of the hydraulic fracturing process plays a key role in the design of hydraulic fracturing. However, most of existing models are overly simplified by neglecting the poroelasticity of rock matrix, which may have a substantial effect on the growth of hydraulic fractures, especially in oil and/or water saturated formations. In this study, we developed a fully coupled finite element model for hydraulic fracture propagation in permeable formations by combining XFEM technique with cohesive zone model, and used it to investigate the effects of poroelasticity on the geometry evolution of single fracture which initiated from an injection point. Fluid flow within the fractures, Darcy flow within the rock matrix, hydraulic fractures propagation, and fluid leak-off into the formation are simultaneously taking into account in the model. Then, the model is validated by comparing the results with available analytical solutions. To understand and quantify the poroelastic effects on the propagation of hydraulic fracture, several cases with different matrix permeability, leak-off coefficients, and bulk modulus of pore fluid are performed. The simulation results show that the total volume of leakage is controlled by the combined action of matrix permeability and leak-off coefficient. The fracture aperture and length decrease with the increase of matrix permeability or leak-off coefficient, while as the bulk moduli of pore fluid increases, the fracture aperture and length tend to increase.

Purpose: This study aimed to assess the repeatability of intraocular lens (IOL) decentration measurements obtained through Pentacam, based on corneal topographic axis (CTA) and pupillary axis (PA), and to evaluate the level of agreement between Pentacam and OPD-Scan III devices in measuring IOL decentration. Methods: In this prospective observational case series, three measurements were performed with Pentacam to evaluate the repeatability of the measurements. The analysis included the calculation of the mean and standard deviations (SD), conducting a repeated measures analysis of variance (rANOVA), and determining an intraclass correlation coefficient (ICC) to assess the repeatability of the measurements. Moreover, Bland-Altman analysis was employed to assess the agreement between Pentacam and OPD-Scan III devices in measuring IOL decentration. IOL decentration measurements were obtained with respect to both CTA and PA. Results: A total of 40 eyes from 40 patients were analyzed. The rANOVA revealed no significant difference among three consecutive measurements of IOL decentration obtained with Pentacam. The mean SD of all parameters ranged from 0.04 mm to 0.07 mm. With CTA as the reference axis, the ICC values for Pentacam measurements of IOL decentration were 0.82 mm for the X-axis, 0.76 mm for the Y-axis, and 0.82 mm for spatial distance. When using PA as the reference axis, the corresponding ICC values were 0.87, 0.89, and 0.77, respectively. The 95% limits of agreement for all IOL decentration measurements were wide when comparing Pentacam and OPD-Scan III. Conclusions: Pentacam demonstrated high repeatability in measuring IOL decentration with respect to both CTA and PA. However, due to poor agreement between Pentacam and OPD-Scan III measurements, caution should be exercised when using data interchangeably between the two devices. [ABSTRACT FROM AUTHOR]

Based on the ANSYS finite element software,the method of dividing the contact area of the four point contact ball bearing is proposed. Establish a uniform thin four point contact ball bearing 1/2 single rolling and ring and the bearing finite element model. Calculation and analysis of the grid cell size on contact characteristics of four point contact ball bearing accuracy influence and solve the bearing finite element model in the static radial force load distribution rules and obtained the thin-walled four point contact ball bearing,the more precise the elliptic contact area shape and four point connected contact state. Research shows that: for the calculation of the contact characteristics and the size of mesh generation approximate to 50 percent of the semi minor axis of the contact ellipse can get more precise results,for thin walled four point contact ball bearings,ball and the inner and outer rolling contact should force,the equivalent force and contact deformation and radial load is nonlinear ascending relationship,contact force and load distribution of the calculated results with the Hertz contact theory should be calculated values are in good agreement. The calculation results are more accurate to simulate the contact characteristics and load distribution of the thin wall four point contact ball bearing.

Compared with the traditional permanent magnet eddy-current couplings,one with slotted conductor disk can force eddy current to flow under a designated route which can improve the transmitted torque and enhance the transmission performance of the device. But if a device with a unreasonable slot numbers or structure,the torque will decrease or the ripple will increase. So the over-all properties of the device will degradation,the regulation reliability will going harder. A comparative analysis of the number of the slot and structure is conducted. At the end,a reasonable slotted number is given and can provide an important reference for the design and application of the permanent magnet eddy-current coupling.

Considering the complexity of technological processes, the serious coupling between multiple processes and the difficulties in optimizing process parameters during the process manufacturing, a multi-process technological parameter fusion optimization method was proposed based on LSTM neural network, XGBoost algorithm and IPSO algorithm. A data preprocessing model was established based on LSTM neural network, and the time series characteristics of processing data were extracted through LSTM neural network, which realized the processing of outlier in process data. And a PSO-XGBoost quality prediction model was constructed by fitting the nonlinear relationship between processing parameters and quality indexes with XGBoost and combining with particle swarm optimization algorithm. Then the output of the quality prediction model was taken as the fitness, and the improved particle swarm algorithm was used for trolling the global optimal processing parameters, which realized the fusion optimization of the quality of process manufacturing. A process production line of an enterprise was taken as an example to verify the effectiveness of the multi-process technological parameter fusion optimization model. [ABSTRACT FROM AUTHOR]

The aim of the study was to study the PK of AST2818 tablets after one oral dose in healthy male subjects on an empty stomach and in a postprandial state and to evaluate the effect of food on AST2818 bioavailability. Sixteen healthy Chinese male subjects were randomly divided into two groups: a fasting-postprandial group and a postprandial-fasting group. The drug was administered once per evaluation at a dose of 80 mg, with an interval of 22 days between the two treatments. The LC-MS/MS method was used to determine the concentrations of AST2818 and its metabolite AST5902. Plasma pharmacokinetic parameters were calculated by noncompartmental analysis (NCA). WinNonlin® version 7.0 was used to analyse PK parameters, and SAS version 9.4 was used for statistical analyses. After a meal, the peak concentration of alflutinib increased by approximately 53%, and the AUC increased by approximately 32%; The peak concentration of its metabolite AST5902 decreased by approximately 20%, and the AUC decreased by approximately 8%. There was no significant change in peak time. The peak AST5902 concentration and AUC 0-∞ were 27.4% and 71.4%, respectively, of that of alflutinib. None of the subjects experienced serious AEs, and both fasting and high-fat meal administration were safe. There was no statistically significant difference between groups in AEs ( P = 0.102, RR = 1.40) or adverse reactions ( P = 0.180, RR = 1.30). The effects of food may not need to be considered for the clinical use of alflutinib. No serious AEs occurred, and drug administration was safe and tolerable after fasting or a high-fat meal.