Every operating system executes in a virtual environment, and there might be (and normally are) several instances of different operating systems running at the same time.

每个操作系统都在一个虚拟环境中运行，因此可能会出现(实际上也会出现)几个不同的操作系统实例同时运行的情况。

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Being aimed to the application environment of telecommunication products and the operating systems differences, operating system Support (OSS) subsystem is designed and implemented.

针对操作系统之间的差异和电信产品的应用环境，我们设计并实现了操作系统支撑子系统(oss)。

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In this virtual environment, still need to simulate the hardware device, install the Guest operating system, and also need to modify the operating system kernel.

在这种虚拟环境下，依然需要模拟硬件设备，安装Guest操作系统，并且还需要修改操作系统的内核。

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Program Streamlines Content Development Environment and Expands the World of PlayStation to Open Operating System Based Portable Devices.

ENGADGET: PlayStation Suite's 'open beta' SDK available to download now

True, there have been some complaints from those who see the new operating system as an uneasy mix of the new mobile world and the old desktop environment, but Microsoft seems confident that all is going to plan.

BBC: Windows boss shown the door