写译 — 计算机系统分层结构的划分？

• Author : Cyan_RA9
• 和大家分享英语写译，包括计算机英文教材，计算机基础，中英文诗词，英文名著，日常对话等，每一篇文章 我都会分别给出“原文内容”，“第一版翻译” 和 “第二版翻译”，以及“生词整理”共四部分。
• 写译 — 计算机系统分层结构的划分？

【原文内容】

• 计算机系统分层结构如下图所示：
• 由上图可知，操作系统是最基本的系统软件，是计算机系统各类软硬件资源的管理者；它位于用户层和硬件层之间，向上提供服务、向下管理资源。
• 进程间的切换无法直接通过硬件实现，因此还需要一层系统软件来对处理器和硬件资源进行抽象改造，这一层系统软件即为操作系统内核，内核是一组运行在内核态的程序模块。
• CPU中有一个寄存器叫＂程序状态字寄存器（PSW）＂，其中有个二进制位，可用1表示”内核态"，0表示"用户态"，亦可反之。

【第一版翻译：（润色前，手译）】

• The layered Architecture of Computer Systems is shown in the diagram below:
  
• From the figure hereinabove, it can be observed that Operating System is the most fundamental system software, simultaneously the regulator of all of resources including both software resources and hardware resources within computer; It's between the user-layer and the hardware-layer, offering services to the layer above and managing resources of the layer below.
• The switching between processes can't be fulfilled directly by hardware, so a system software layer is indispensable to abstract and adapt Processor and other hardware resources, and this system software layer is termed OS kernel which is actually a set of program modules running in the Kernel-Mode.
• Within the CPU, there is a register called the Program Status Word(PSW) register. One of its bits can be used to represent "Kernel mode" with a 1 and "User mode" with a 0, or vice versa.

【第二版翻译：（润色后，雅思水准）】

• The layered Architecture of Computer Systems is shown in the diagram below:
  
• From the figure hereinabove, it can be observed that the Operating System is the most fundamental system software, simultaneously the manager of all resources including both software and hardware resources within a computer; It is positioned between the user layer and the hardware layer, offering services to the layer above and managing resources of the layer below.
• The switching between processes cannot be fulfilled directly by hardware, so a system software layer is indispensable to abstract and adapt the Processor and other hardware resources; This system software layer is termed the OS kernel which is actually a set of program modules running in the Kernel-Mode.
• Within the CPU, there is a register called the Program Status Word(PSW) register. One of its bits can be used to represent "Kernel mode" with a 1 and "User mode" with a 0, or vice versa.

【生词整理】

• The layered Architecture of Computer Systems：phrase.计算机系统分层结构
• layered architecture：phrase.分层结构，分层体系
• layer：n.层次，层，阶层，阶级
• layered：adj.分层的，层状的
• xxx is shown in the diagram below：phrase.xxx如下图所示
• hereinabove：adv.在上文，上述
• the Program Status Word(PSW) register：n.程序状态字寄存器
• binary bit：n.二进制位

【手译手稿】