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In the digital age, e-commerce has emerged as a transformative force in the domain of rural tourism, infusing traditional practices with renewed dynamism. This study employs the spatiotemporal extreme entropy value method to assess the evolution of rural tourism in China. The investigation delves into the influence of e-commerce on the qualitative enhancement of rural tourism, utilizing a dynamic panel data model to analyze its effects and conducting heterogeneity tests based on geographic and economic criteria. According to the weights assigned by the spatiotemporal extreme entropy method, the quality of rural tourism development in China generally increased between 2013 and 2023, with a notable dip to 0.3005 in 2020. The heterogeneity analysis, implemented through a fixed-effects model, reveals significant positive impacts in both the eastern and central regions at the 5% significance level. Moreover, regions with a medium level of economic development exhibit a robust positive effect, with a regression coefficient of 0.429. The developmental impact of e-commerce on high-quality rural tourism is statistically significant at the 1% level, and all control variables demonstrate significant positive correlations. These findings underscore the substantial role that e-commerce development plays in advancing high-quality rural tourism.

Human factor is an important cause of coal mine accidents. In order to study the regularity in human-caused accidents and to improve the target of human-caused management, text data mining method was used to analyze the accident report text data by WordCloud-LDA according to the accident triggering mechanism, and to construct a human-caused factor system for coal mine accidents. On this basis, the human factor matrix set of coal mine accidents is generated, and the correlation analysis of the human factor matrix set is carried out, and the strong association rules between the human factor and the general accident and the roof accident are obtained. The results show that the study of human factors association rules in coal mines under accident report mining can lead to conclusions on the trend among human factors, and provide a basis for human factors control decisions.

Currently, there's a lack of research on air volume regulation and mine resistance reduction of ventilation system in mine working face. In order to solve the above problem, taking 10303 working face and 33low 02 working face of Jining No.2 Coal Mine as the engineering background, the original ventilation systems in these two areas are optimized and transformed in terms of air volume regulation and mine resistance reduction. The ventilation system diagram of the working face is imported into Ventism software, generating a solid roadway and iterating the calculation to construct a mine ventilation network solution model. The main parameters measured on-site are input into the model for airflow calculation. The errors between calculated relevant data such as flow velocity, temperature, and air volume in the roadway obtained and the on-site measurement data are within the standard range. From the measurement results of mine ventilation resistance, it can be seen that the original ventilation system has the following problems. The setting of the regulating air wall at the south wing stone gate is unreasonable. The actual air supply volume of 33low02 working face is less than the ideal air volume. The ventilation route of the south wing -740 horizontal track main roadway is long. It is affected by the parallel intake of auxiliary transportation roadways, resulting in high resistance in the south wing return air main roadway. In order to solve the above problems, three renovation measures are proposed. ① A closed air door is installed at the intersection of the south wing return air stone gate and the north wing belt conveyor roadway. The original air window area of the south wing belt conveyor roadway and return air stone gate is adjusted to 2.9 m2. ② A 0.1 m2 adjustable wind window is installed at the intersection of the extension of the third mining area's track downhill and the 33low02 connecting roadway. ③ The 0.9 m2 adjustable air window at the interface between the pipe duct in the 11th mining area and the south wing -740 horizontal track roadwayhas been changed to 2.4 m2,so as to reduce the air volume of the south wing -740 horizontal track roadway and increase the parallel air volume of the auxiliary transportation roadway. The simulation results of the modified ventilation system show that the resistance of the southern wing -740 horizontal track main roadway has been reduced by 32.7%. The air volume of the 33low02 working face has been increased by 19.8%. The total resistance of the mine ventilation route has been reduced by 6.4%. The on-site measurement results of the modified ventilation system show that the average relative error between the measured air volume and numerical simulation results is 1.28%. The average relative error between the measured resistance and numerical simulation results is 2.52%. The optimized simulation results are basically consistent with the on-site test results. The range of changes in air volume and resistance of the intake shaft before and after the entilation system adjustment is not significant. The air volume at the measuring point of the return air shaft decreases, and resistance decreased. The optimized measured air volume at the 33low02 track connecting roadway and the measuring points of the working face increase by 25.3% and 21.4%, respectively, and the resistances increase by 57.4% and 41.1%. The optimized measured air volume at the south wing -740 horizontal track roadway decreases by 20.3%, and resistance decreases by 36.6%. After the renovation, the air volume of the working face and the total resistance of the mine have achieved the expected results.

The influence of Zr and Ti on the inclusions, microstructure, and mechanical properties of three sets of steel prepared using a vacuum induction melting furnace is analyzed. In steel without Zr and Ti, MnS is mainly distributed in the grain boundary with a rod‐like or dendritic morphology, an average diameter of 10 μm, and a quantity of 2.08 × 104 m−3. After alloying with Zr and Ti, MnS in steel is evenly distributed and adopted a blocky or spherical morphology with an average diameter of 7.2 μm and a quantity of 11.01 × 104 m−3. The oxygen content in steel do not have a remarkable impact on the MnS morphology. ZrO2 and Ti2ZrO6 formed in steel display a slight lattice disregistry with MnS. During solidification, MnS precipitates easily as types I and III MnS, with oxides serving as the core. The MnS composite exhibits remarkable deformation resistance during forging. The addition of Zr and Ti increases the proportion of intragranular ferrite in steel and decreases the pearlite lamellae spacing and average grain size, increasing the yield strength from 745 to 820 MPa and the impact energy from 21 to 56 J at room temperature. Overall, the addition of Zr and Ti considerably improves the mechanical properties of steel. [ABSTRACT FROM AUTHOR]

Summary: There are many different index structures for service repositories, such as sequential index, inverted index, and multilevel indices that include three deployments. Different service sets maybe have different characteristics that may affect performance from different aspects. For a given service set, which index structure is the most optimal one? To address these issues, this paper analyses five indexing models and proposes expectation of traversed service count to estimate performance of service retrieval. Based on these expectation formulas, an optimal deployment method can be identified to maximize efficiency of service retrieval. Our experiments first validate correctness of the proposed formulas and then validate the effective of the optimal method. [ABSTRACT FROM AUTHOR]