Military petroleum equipment, as the special device a nd tool for petroleum storage, transportation, filling, chemical analysis, detec tion and maintenance for the army, is an important means and basis of petroleum in...Military petroleum equipment, as the special device a nd tool for petroleum storage, transportation, filling, chemical analysis, detec tion and maintenance for the army, is an important means and basis of petroleum indemnificatory. To adapt to modern war in high-tech conditions, the petroleum equipment have to develop towards higher reliability, adaptability, maneuverabil ity, standardization, container and cell type with versatile multi-functions. As a new design theory and design process, concurrent engineering may prod uce remarkable benefit when applying to product development. With the aid of the state-of-the-art modeling and simulation technology, it foresees the future or even the whole life cycle of the products designed. Based on wide statistics and survey, the product design period is reduced by 1/2～1/3 with concurrent des i gn process. The application of concurrent design process in new petroleum equi pment development shall greatly accelerate the petroleum equipment updating an d promote their indemnificatory.展开更多
Engine engineering database system is an oriented C AD applied database management system that has the capability managing distributed data. The paper discusses the security issue of the engine engineering database ma...Engine engineering database system is an oriented C AD applied database management system that has the capability managing distributed data. The paper discusses the security issue of the engine engineering database management system (EDBMS). Through studying and analyzing the database security, to draw a series of securi ty rules, which reach B1, level security standard. Which includes discretionary access control (DAC), mandatory access control (MAC) and audit. The EDBMS implem ents functions of DAC, MAC and multigranularity audit. DAC solves the problems o f role inheritance, right contain, authorization identify and cascade revoke, et c; MAC includes subject and object security setup rule, security modify rule and multilevel relation access operation rule, etc; Audit allows making the sub ject, object or operation type as different audit object to implement flexible a nd multigranularity audit method. The model is designed act as a security agent to access daemon database. At present, the model is implemented which runs on th e Windows 2000 environments.展开更多
文摘Military petroleum equipment, as the special device a nd tool for petroleum storage, transportation, filling, chemical analysis, detec tion and maintenance for the army, is an important means and basis of petroleum indemnificatory. To adapt to modern war in high-tech conditions, the petroleum equipment have to develop towards higher reliability, adaptability, maneuverabil ity, standardization, container and cell type with versatile multi-functions. As a new design theory and design process, concurrent engineering may prod uce remarkable benefit when applying to product development. With the aid of the state-of-the-art modeling and simulation technology, it foresees the future or even the whole life cycle of the products designed. Based on wide statistics and survey, the product design period is reduced by 1/2～1/3 with concurrent des i gn process. The application of concurrent design process in new petroleum equi pment development shall greatly accelerate the petroleum equipment updating an d promote their indemnificatory.
文摘Engine engineering database system is an oriented C AD applied database management system that has the capability managing distributed data. The paper discusses the security issue of the engine engineering database management system (EDBMS). Through studying and analyzing the database security, to draw a series of securi ty rules, which reach B1, level security standard. Which includes discretionary access control (DAC), mandatory access control (MAC) and audit. The EDBMS implem ents functions of DAC, MAC and multigranularity audit. DAC solves the problems o f role inheritance, right contain, authorization identify and cascade revoke, et c; MAC includes subject and object security setup rule, security modify rule and multilevel relation access operation rule, etc; Audit allows making the sub ject, object or operation type as different audit object to implement flexible a nd multigranularity audit method. The model is designed act as a security agent to access daemon database. At present, the model is implemented which runs on th e Windows 2000 environments.
