Schedule management is an important approach to guarantying the product development plan.

进度管理是保证产品开发按计划完成的重要手段。

The specific measures and suggestions on guarantying the silica brick quality for coke ovens are put forward.

提出了确保焦炉硅砖质量的具体措施和建议。

But due to the characteristics of MANET, implementing VoIP services and guarantying its voice quality are faced with many challenging issues.

但是由于无线移动自组织网自身的特点，使得实现IP语音技术并且保证语音质量会面临很多问题。