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In this paper, aiming at the reliability analysis and optimization of jth series marine low-speed diesel engine supercharger of Chongqing JIANGZENG Shipbuilding Heavy Industry Co., Ltd., a response surface mathematical model is constructed by using 62 groups of dispersive simulation analysis data to verify the accuracy and effectiveness of the mathematical model. Based on this, Monte Carlo sampling is carried out to obtain the reliability of turbine disk is 0.943, and the reliability of turbine blade is 0.96 Reliability optimization space. Based on NSGA-II multi-objective genetic algorithm, the reliability of turbine disk and turbine blade is optimized by taking the stress value and machining cost of turbine disk and turbine blade as the objective function. The reliability of turbine disk and turbine blade is 1, the stress value of turbine blade is optimized by 4.7941%, the stress value of turbine disk is optimized by 3.0136%, the machining cost of turbine blade is optimized by 15.5087%, and the machining cost of turbine disk is optimized by 3.9907%. Finally, the results of genetic algorithm and simulation analysis are compared, the difference is less than 5%, which shows that the data based on NSGA-II multi-objective genetic algorithm has practical application reference value.

With the increasingly widespread use of email and the increasing importance of email data, email archiving has become necessary for mail management. In view of this, we propose a solution of the design and implementation of email archiving system based on J2EE. This solution researches and analysis some key technologies of mail archiving such as mail backup, full-text indexing, email recovery an so on first, and then designs a mail archiving system based on J2EE, resolves the mail real-time backup, full-text search and others. Finally, this system has been applied in actual mail archiving work. Experimental results show that the mail archiving system based on J2EE can achieve real-time email backup and rapid email recovery, this solution can effectively help enterprise users to resolve the problem of email archiving.

To prevent data loss and damage in MySQL database for a variety of causes, to ensure the normal and efficient operation of information systems and websites based on MySQL databases, this paper takes China Agricultural University website as an example, to explore how to develop reasonable backup and recovery strategies to build a highly available and highly reliable MySQL database backup and recovery system. Based on MySQL master-slave replication technology, this system implements real-time synchronization of data and automatic switching between master and slave database servers, which ensures the high availability of database when master database fails, meanwhile, by using logical backup technology which combines full backup with incremental backup, this system achieves full recovery of data to ensure the high reliability of database when data misuse occurs.

This thesis studies the impact of ultimate controlling shareholders on the earnings quality of the listed companies. Taking A-share companies that went public during 2008-2011 as samples and measuring earnings quality with discretional accruals, our study discovers that the ultimate controlling shareholders' ownership proportion, the deviation of ownership and control rights as well as the shareholding ratio of the biggest investor of circulation shares have significant explanatory effects on earnings quality. Specifically, in public companies, the discretional accruals are in inverted U-shaped correlation with the ownership proportion of the actual controllers, in significant positive correlation with the deviation of the actual controllers' two rights, and in significant negative correlation with the shareholding ratio of the biggest investor of circulation shares. Based on these conclusions, this thesis provides a number of policy suggestions.

Based on the conclusion that the contribution of correlated decay of two vacancies in atoms is small，the de-excitation process of Mg1+(1s-1) hollow magnesium ions with single K-vacancy and Mg2+(1s-2) double K-vacancy were treated by applying the radiative-single Auger - double Auger cascade model（RACDA）. The final-charge-state distribution(FCSD) of these hollow ions were calculated，and compared with that obtained with the radiative-single Auger cascade model（RAC）. The probability of tetravalent ion production via the de-excitation of Mg1+(1s-1) obtained by RACDA model is considerable，but tetravalent ion is not produced in the by RAC model. The probability of hexavalent ion production via the de-excitation of Mg2+(1s-2) obtained by RACDA model is very large，but hexavalent ion is not produced in the RAC model.

On the basis of a previous model of radiative-Auger-cascade for calculation of final-charge-state distributions of hollow ions, a new model of radiative-Auger-double Auger-cascade has been constructed by including double Auger process, and was applied to study the final-charge-state distribution in the production of Ar+(1s-1) (argon ion with an initial 1s hole) and Ar+(2s-1) (argon ion with an initial 2s hole). Comparing with the previous calculations and experiments, the present results show excellent agreement.