A wireless sensor network is a distributed collection of resource constrained tiny nodes capable of operating with minimal user attendance. Communication circuit is normally the most power consuming part of sensor node. Depending on the application, the node may have on board various extra hardware components with even higher power consumption. These components can impose restrictions in terms ...

Energy consumption modelling by state based approaches often assume constant energy consumption values in each state. However, it happens in certain situations that during state transitions or even during a state the energy consumption is not constant and does fluctuate. This paper discusses those issues by presenting some examples from wireless sensor and wireless local area networks for such ...

Compared with Computational Grid, the Information Grid currently has no clearly definition. In terminology of the Shanghai Information Grid, to meet the requirement of Information Grid, we design a QoS-aware Information Service which can provide efficient search ability and reliable Index Service and the Information Grid Portal which acts as an access point to Information

We note that there is an exception to the general arguments that no falsifiable predictions can be made, on the basis of of presently available data, by applying the weak anthropic principle (WAP) to the landscape of string theory. If there are infinitely more vacua in the landscape for one sign of a parameter than the other, within an anthropicaly allowed range, then under very weak assumption...

Final approval of the IEEE 802.11 standard for wireless local area networking (WLAN) last year and rapid progress made toward higher data rates have positioned this technology to fulfill the promise of truly mobile computing. While wired LANs have been a mainstream technology for at least fifteen years, WLANs are uncharted territory for most networking professionals. There are some important di...

2 This research illustrates an advanced wireless switching platform to let users can convey their data through wireless networking by keeping original session. That is, this platform can switch between Wi-Fi and 3G communication channels seamlessly. Such a platform is adapted from the healthcare enterprise to personal health monitoring.

We compare the usage of a Digital Library with many different categories of collections, by examining its log files for a period of twenty months, and we conclude that the access points that the users mostly refer to, depend heavily on the type of content of the collection, the detail of the existing metadata and the target user group. We also found that most users tend to use simple query stru...

It is well known that in IEEE 802.11 networks, the assignment of low-rate and high-rate users to the same access point significantly degrades the performance of the high-rate users. Our objective is to investigate the implications of the above performance degradation on the incentives for handover between 802.11 wireless local area networks with overlapping coverage. Our focus is on the incenti...

Wireless Sensor Networks (WSN) are highly distributed self organized systems. The basic idea of sensor network is to disperse tiny sensing devices; which are capable of sensing some changes of incidents/parameters and communicating with other devices, spread over a specific geographic area for some specific purposes like environmental monitoring, surveillance, target tracking etc. By combining ...