background: this study aimed to evaluated trends for iron and manganese concentrations in wells, reservoirs, and water distribution networks in qom city during the summer of 2012. methods: this was a cross-sectional study. the studied scopes consisted of groundwater (60 wells), reservoirs (10 tanks), and water distribution network (33 points). one sample was taken from each source monthly. stat...

Peer-to-peer networks have often been touted as the ultimate solution to scalability. Although cooperative techniques have been initially used almost exclusively for content lookup and sharing, one of the most promising application of the peer-to-peer paradigm is to capitalize the bandwidth of client peers to quickly distribute large content and withstand flash-crowds (i.e., a sudden increase i...

The use of mobile data services is in high demand ever since the advent of smartphones and is expected to increase further with the evolution of various services and applications for future mobile devices. This excessive use of data has caused severe bottlenecks within the mobile networks due to overloading. The route towards network upgrades is an expensive one especially due to the high licen...

Future wireless IP networks will scale to millions of heterogeneous terminals and provide seamless and ubiquitous content services. However, wireless networks and terminals have drastically different characteristics than their wireline counterparts in terms of bandwidth availability, mobility, processing/display limitation and power consumption requirements, and some key assumptions that existi...

Dedicated short range communication (DSRC) relies on secure distribution to vehicles of a certificate revocation list (CRL) for enabling security protocols. CRL distribution utilizing vehicle-to-vehicle (V2V) communications is preferred to an infrastructure-only approach. One approach to V2V CRL distribution, using rateless coding at the source and forwarding at vehicle relays is vulnerable to ...

A Content Distribution Network (CDN) is an overlay network where servers replicate contents and distribute client’s requests with the aim at reducing delay, server load and network congestion, hence improving the quality of service (QoS) perceived by end clients. Because of server constraints and costs involved in the replication process, it is not reasonable to replicate the contents over the ...

conventional passive distribution networks are changing to modern active distribution networks which are not radial. conventional load flow methods should be modified for new distribution networks analysis. in modern distribution networks distributed generation (dg) units are embedded with conventional and/or renewable resources. dg units are generally modeled as pv or pq nodes which inject ...