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The concentrated load endured by the locking system during the weapon mounting and release procedures may lead to mechanical wear in hinges and kinematic pairs, thereby influencing the functional reliability of the weapon rack mechanism system. This study aims to investigate the impact of kinematic pair wear evolution on the reliability of the locking system. Firstly, a rigid-flexible coupling multi-body dynamics model of the locking system was established to simulate the dynamic behaviors of the rack under different loading conditions. Moreover, the wear amounts of the main kinematic pairs were precisely calculated by the Archard wear model to provide data support for the subsequent reliability analysis. Subsequently, the response surface method was employed to design the orthogonal experiments for the reliability analysis of the locking system, and the reliability degradation law of the locking system within the design lifespan was obtained through the Monte Carlo method simulation. The research findings indicate that the wear of kinematic pairs has a significant effect on the motion function and accuracy of the mechanism. The motion reliability of the mechanism can be maintained above 99% within the design lifespan. Nevertheless, when the usage time exceeds twice the design lifespan, the reliability drops significantly to approximately 85%, and the influence degrees of different wear positions on the reliability were obtained through the sensitivity analysis. The research results not only provide a scientific basis for the optimal design of the locking system but also offer a novel perspective and method for the reliability assessment and maintenance strategy of the weapon rack locking system.

In keeping with contemporary demands, the integration of political and ideological education with student management empowers students to actively embrace the establishment of a superior ideological culture in a more open and laid-back learning environment. The creation of an extensive index system enables the integration and collaboration of political and ideological instruction and student management duties in colleges and universities. The theory of system coupling is used to discuss the level of synergy and consistency of system development. The subjective empowerment method uses the FIAHP technique to determine the subjective weight of the standard. The objective weight of the indicator is determined by using the pull-out grade method. The LPE-SMW coupling coordination model is constructed by combining the weights of the two indexes to solve the weights. The coupling coordination level is evaluated and examined in order to confirm the efficacy of the coupling coordination model in examining the development and integration between political and ideological education and student management in colleges and universities. The coupling degree of coordination in the eastern region is approximately 0.65, and the degree of coupling coordination of the LPE-SMW in the central region has a mean yearly increase of 0.43% over the 20 years, according to the results of the smoothness test of each variable of the LPE-SMW linking coordination degree model, which shows differences at the 1% level. The linking coordination model offers a fresh approach to the creation of successful integration between political and ideological education and student management in higher education by offering a thorough examination of the relationship between the two.

As an important tributary of the Yangtze River basin, the Jialing River Basin (JRB) has a variable topography and fragile ecological environment. Under the influence of climate warming and human activities, the runoff and vegetation cover of the area are undergoing significant changes. For evaluating the impact of different factors on vegetation and streamflow variation in the JRB, the univariate linear regression method was employed to analyze the variation trend of streamflow and vegetation, and a heuristic segmentation algorithm was applied for identifying the mutation year of streamflow and NDVI time-series data in the JRB. Then, the influence degree of different factors on streamflow variation in the JRB was calculated by the Budyko equation and elastic coefficient method. Finally, the contribution rates of different factors to vegetation variation in the JRB were calculated by the multiple linear regression method. The results indicated that the mutation year of streamflow and NDVI time series data were 1985 and 2006, respectively. The contribution rates of climate factors and human activities to streamflow change in the JRB were 42.7 and 57.3%, respectively. The contribution rates to vegetation change were 28.89 and 71.11%, respectively. In general, human activities are the main driving force leading to runoff and vegetation changes in the JRB. This study can provide a theoretical basis for the ecological environment protection and water resources management of the JRB.

To provide essential data for the separation of diethoxymethane and system water using mesityl oxide as the extractant, in this paper, the liquid-liquid equilibrium data of the ternary system of ‘mesityl oxide + diethoxymethane + water’ was measured at 303.2 K, 313.2 K and 323 K under normal pressure. The experimental results showed that partition coefficient and separation factor were both larger than 1, indicating that diethoxymethane and water could be well separated with mesityl oxide. The linear correlation coefficient of Bachman and Hand equation was larger than 0.99, indicating that our experimental data has good reliability. At the same time, the binary interaction parameters of the model were obtained by correlating the experimental data with the NRTL and UNIQUAC models. The relative root mean square error (RMSD) of the experimental value and the calculation formula was less than 0.79%, indicating that both the NRTL and UNIQUAC models can be well associated with experimental data.

In order to grasp changes of the danger of coal and gas outburst, factors of coal seam gas emission were analyzed, R/S analysis method was used to study gas emission of coal mine tunnel, and the following conclusion was obtained: gas emission time series have fractal characteristics, when it is detected that Hurst index is decreasing and has great volatility, it indicates abnormal gas emission will occur, so certain safety precautions should be taken in advance.

Abstract Background In a previous hospital-based study, conjunctivochalasis was diagnosed in 85.24% of 1416 patients aged 1 to 94 years and in 98.5% of patients aged 60 or older. This report is the first to present data from a large scale epidemiologic study on conjunctivochalasis in a community-based population, thereby helping to better identify the severity of conjunctivochalasis in the general population. Methods This community-based epidemiologic study was conducted to evaluate prevalence rates and related factors of conjunctivochalasis among people over 60 years old in the CaoYangXinCun community, Shanghai, China. Cluster sampling was used in randomly selected local residents aged no less than 60 years. A cross-sectional study using a slit-lamp ophthalmoscope for examination was carried out from September 2008 to October 2008. A modified grading system based on the well-accepted Meller and Tseng's system was used. SPSS10.0 software was used for data and statistical analysis. Results A total of 2110 residents took part in this study, with a response rate of 94.85%. Among these, 930 cases were confirmed as conjunctivochalasis, with a prevalence rate of 44.08%. The prevalence rate increased with age (X2 = 10.44, P < 0.01). A total of 1762 eyes were confirmed as conjunctivochalasis eyes. Of these eyes, 943 were classified as Grade I (53.52%), 647 as Grade II (36.72%), 162 as Grade III (9.19%), and the remaining 10 eyes as Grade IV (0.57%). The conjunctiva usually accumulated on the nasal and temporal areas of the conjunctival sac (944 eyes, 53.58%). Conclusions Although the rate estimated in the present study is not as high as reported in the former hospital-based study, conjunctivochalasis is considered a common age-related eye disease, deserving more attention to its early diagnosis.