软件系统是对现实世界模型的反映,现实世界的变化要求软件系统进行相应的演化.软件演化是软件系统的动态行为,贯穿整个软件生命周期,从系统的初始开发阶段到最终的软件维护.软件演化包括软件系统的过程,方法,技术,组织方式等的演化.基于软件构架和构件的开发方法实现的系统比传统的开发方法具有更好的易演化性.软件构架高度...
To extend the usage scope of an 802.11DCF-based wireless LAN power-saving MAC protocol 802.11PS to a multi-hop mobile environment,a modified version called 802.11NPS is proposed.It applies a packet-driven dynamic switching-off mechanism to the wireless network interface card to save power.By de...
aAbstract—This paper studies an important problem in the IEEE 802.11 distributed coordination function (DCF)-based wireless local area network (WLAN): how well can the network support quality of service (QoS). 抽象这篇文章在IEEE 802.11分布的协调作用DCF -基于无线 ()区域网WLAN学习一个重要 (问题...
MAC protocol for wireless Ad hoc network based on IEEE802.11一种基于IEEE802.11的无线自组网MAC协议 Based on the IEEE802.11DCF, a Medium Access Control (MAC) protocol was proposed for wireless ad hoc network. It consisted of two key mechanisms: network ad... LI Xiaofeng,YAN Chuping,李晓峰,....
FMU-DCM80, 80KM DCF-based Passive Dispersion Compensation Module, LC/UPC Dispersion Compensation Module (DCM) is designed to fix the form of optical signals that are deformed by chromatic dispersion. The module offers a high level of compensation while maintaining a low flat insertion loss as we...
We propose Fast Flooding in Power Save Mode (FFPSM), a modification of IEEE 802.11 power save mode operation for Mobile Ad hoc NET works (MANET). The previous works for the power save mode operation usually focused on shortening the duration of the awake
Fast Flooding in Power Save Mode of IEEE 802.11 DCF Based Mobile Ad Hoc Networks Myung-Hwan Seo1 , Hyeon-Ju Yoon2 , and Joong-Soo Ma1 1 Information and Communications University, 103-6, Munji-Dong, Yusong-Gu, Daejeon 305-714, S. Korea http://mm.icu.ac.kr 2 Korea Advanced Institute...
Function,DCF),它是基于冲突避免的载波侦听 多路访问(CSMA/CA)机制,由冲突导致的数据 重传遵循二进制指数退避规则;另一种是基于轮询 的点协调功能(PointCoordinationFunction,PCF)。 由于PCF实现复杂,实际中大多采用DCF。 DCF定义了两种数据接入模式:基本模式和 RTS/CTS握手模式。二者的区别在于,后者在发 送数据前,...
Our findings show that the blocking efforts by Google and Microsoft have resulted in a 67% drop in the past year in web-based searches for CSEM. Additionally, our findings show that mobile devices are a substantial platform for web-based consumption of CSEM, with tablets and smartphones ...
How the ac effective permeability (μe) correlates with dc magnetic properties over a wide frequency range of 1 to 1000 kHz was studied, in an effort to understand the magnetization behavior of the Co‐based amorphous alloy of Metglas 2714A subject to an ac magnetic field. In the low‐frequ...