One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. Th...One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. The recent trend in operating system development is adopting microkernel architecture which holds such advantages as microminiaturization, modularity, portability and extendibility. The performance of I/O subsystem is currently receiving considerable research attention. Object-orientation offers an approach to application development in which software system can be constructed by composing and refining the pre-designed plug-compatible software components.It also starts with some basic notions fairly well accepted in computer science, namely encapsulation and reuse. In this paper, a new object-oriented real-time I/O subsystem model has been designed.In this model, the traditional I/O subsystem framework is discarded and a stream mechanism based on the object-oriented concept is introduced. In addition, the I/O requests are classified according to their time emergency to obtain real-time performance. So, this model meets such satelliteperformance requirements as reliability, flexibility, portability and real-time performance.展开更多
随着访问控制技术的发展以及安全需求的多样化,访问控制模型的组合应用日益成为安全操作系统设计的重要目标,由此对策略描述语言提出了统一易用的新要求。通过对现有安全策略语言和访问控制模型的研究,设计了一种应用于安全操作系统领...随着访问控制技术的发展以及安全需求的多样化,访问控制模型的组合应用日益成为安全操作系统设计的重要目标,由此对策略描述语言提出了统一易用的新要求。通过对现有安全策略语言和访问控制模型的研究,设计了一种应用于安全操作系统领域的访问控制策略语言EGACPL(Easily Use andGeneral Access Control Policy language)。EGACPL采用结构化以及面向对象的设计思想,便于开发者理解和使用;统一描述策略元素和安全规则,支持多种访问控制模型,体现了良好的通用性。展开更多
文摘One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. The recent trend in operating system development is adopting microkernel architecture which holds such advantages as microminiaturization, modularity, portability and extendibility. The performance of I/O subsystem is currently receiving considerable research attention. Object-orientation offers an approach to application development in which software system can be constructed by composing and refining the pre-designed plug-compatible software components.It also starts with some basic notions fairly well accepted in computer science, namely encapsulation and reuse. In this paper, a new object-oriented real-time I/O subsystem model has been designed.In this model, the traditional I/O subsystem framework is discarded and a stream mechanism based on the object-oriented concept is introduced. In addition, the I/O requests are classified according to their time emergency to obtain real-time performance. So, this model meets such satelliteperformance requirements as reliability, flexibility, portability and real-time performance.
文摘随着访问控制技术的发展以及安全需求的多样化,访问控制模型的组合应用日益成为安全操作系统设计的重要目标,由此对策略描述语言提出了统一易用的新要求。通过对现有安全策略语言和访问控制模型的研究,设计了一种应用于安全操作系统领域的访问控制策略语言EGACPL(Easily Use andGeneral Access Control Policy language)。EGACPL采用结构化以及面向对象的设计思想,便于开发者理解和使用;统一描述策略元素和安全规则,支持多种访问控制模型,体现了良好的通用性。
