Impact Analysis of Different Scheduling and Retransmission Techniques on an Underwater Routing Protocol

Despite many advances in the area of Underwater Wireless Sensor Networks (UWSN) during the last years, still many challenges need to be successfully tackled before large-scale deployment of underwater sensor networks becomes a reality. UWSNs usually employ acoustic channels for communications, which compared with radio-frequency channels, allow much lower bandwidths and have longer propagation delays. In the past, different methods have been proposed to define how a node must acquire the channel in order to start a transmission. Given the large propagation delays of underwater communication channels, a TDMA-based approach may need big time-guards. On the other hand, the very same large propagation delay increases the occurrence of the hidden terminal problem in a CSMA-based approach. In this paper, impacts of utilization of different scheduling and retransmission techniques on an underwater routing protocol will be analyzed. This analysis, in which energy consumption, packet delay, number of duplicate packets, and packet loss are considered, will be carried out by means of simulation using the Network Simulator 3 and a subset of EDETA (Energy-efficient aDaptive hiErarchical and robusT Architecture) routing protocol recently adapted to UWSN

Effect of replacing sucrose with tagatose and isomaltulose in Mandarin orange marmalade on rheology, colour, antioxidant activity, and sensory properties

The aim of this study was to make mandarin orange marmalades, in which sucrose is replaced by sweeteners, such as tagatose and isomaltulose, which are non-cariogenic and have a low glycemic index. Analyses of rheology, colour, antioxidant activity, microbiology, and sensory properties were carried out on marmalades on their first day, and after 90, 180, and 360 days of storage. The results showed that marmalades made with healthy sweeteners had a less elastic character and were thinner in consistency than those made with sucrose. Lightness was shown to be highest in mandarin orange marmalades made with tagatose, although colour was stable for 180 days to one year of storage. Tagatose also enhanced the antioxidant activity of these marmalades. All marmalades were microbiologically stable. Finally, marmalades made with tagatose alone scored the highest for global acceptance and intention of buying by consumers

Measurement of the proton structure function F2 at low Q2 in QED compton scattering at HERA.

The proton structure function F2(x,Q2) is measured in inelastic QED Compton scattering using data collected with the H1 detector at HERA. QED Compton events are used to access the kinematic range of very low virtualities of the exchanged photon, Q2, down to 0.5 GeV2, and Bjorken x up to 0.06, a region which has not been covered previously by inclusive measurements at HERA. The results are in agreement with the measurements from fixed target lepton–nucleon scattering experiments

A measurement of the proton structure function F-2(x, Q(2)) at low x and low Q(2) at HERA

The results of a measurement of the proton structure function F_2(x,Q^2)and the virtual photon-proton cross section are reported for momentum transfers squared Q^2 between 0.35 GeV^2 and 3.5 GeV^2 and for Bjorken-x values down to 6 10^{-6} using data collected by the HERA experiment H1 in 1995. The data represent an increase in kinematic reach to lower x and Q^2 values of about a factor of 5 compared to previous H1 measurements. Including measurements from fixed target experiments the rise of F_2 with decreasing x is found to be less steep for the lowest Q^2 values measured. Phenomenological models at low Q^2 are compared with the data.Comment: 27 pages, 10 Figure