We have carried out saturation spectroscopy of cyclotron resonance in a semiconducting InAs/Al Ga Sb single quantum well using the UCSB free electron laser and have extracted an effective Landau level lifetime using an n-level rate equation model. The effective lifetime shows strong oscillations ('an order of magnitude) with frequency. Minima are shifted to higher frequencies than those given b...

A wireless sensor network consists of a large number of distributed independent sensors. One of the major challenges is to use energy conserving routing algorithms that can find paths which consume the minimum energy. Recent researches on maximising the lifetime of WSN, like the online maximum lifetime (OML), and capacity maximisation (CMAX) heuristic were intended to do so. Others applied a ne...

wireless sensor networks are the new generation of networks that typically are formed great numbers of nodes and the communications of these nodes are done as wireless. the main goal of these networks is collecting data from neighboring environment of network sensors. since the sensor nodes are battery operated and there is no possibility of charging or replacing the batteries, the lifetime of ...

Most of the protocols for enhancing the lifetime of wireless sensor networks (WSNs) are of a homogeneous nature in which all sensors have equal amount of energy level. In this paper, we study the effect of heterogeneity on the homogeneous protocols. The ALBPS and ADEEPS are the two important homogeneous protocols. We incorporate heterogeneity to these protocols, which consists of 2-level, 3-lev...

The isotope effect and excitation-energy dependence have been measured in the oxygen K-edge x-ray emission spectrum (XES). The use of XES to monitor core decay processes provides information about molecular dynamics (MD) on an ultrafast time scale through the O1s lifetime of a few femtoseconds. Different nuclear masses give rise to differences in the dynamics and the observed isotope effect in ...

Battery lifetime has become one of the top usability concerns of mobile systems. While many endeavors have been devoted to improving battery lifetime, they have fallen short in understanding how users interact with batteries. In response, we have conducted a systematic user study on battery use and recharge behavior, an important aspect of user-battery interaction, on both laptop computers and ...

In this paper an Energy Efficient Clustering Scheme with Mobile Sink (EECSMS) for Heterogeneous Multilevel Wireless Sensor Networks is proposed. In EECSMS, the cluster-heads (CHs) are elected by a probability based on the ratio between residual energy of each node and the average energy of the network, the sink or base station (BS) moves towards each CH by a distance proportional to that CH’s p...

Nowadays, the technology intends to use materials such as magnesium alloys due to their high strength to weight ratio in engine components. As usual, engine cylinder heads and blocks has made of various types of cast irons and aluminum alloys. However, magnesium alloys has physical and mechanical properties near to aluminum alloys and reduce the weight up to 40 percents. In this article, a new ...

The Wireless sensor networks have been deployed in an wide range of applications in environmental monitoring, target tracking, etc. The sensor networks have an major problem concerned with energy efficiency and lifetime of the network. The Energy consumed by the nodes should be less which prevents the earlier death of sensor nodes due to drained energy level. Several techniques have been used t...