The spaceborne ESA-mission CHRIS (Compact High Resolution Imaging Spectrometer) on-board PROBA-1 (Project for On-board Autonomy) delivers multi-directional data sets that contain spectral, directional, spatial and multi-temporal information. CHRIS/PROBA data have been acquired over two well documented test sites in Switzerland (Swiss National Park (SNP) and Vordemwald (VOR) since 2003 and allow...

This paper shows some insecurities in Xu’s forward secure multi-proxy signature scheme. There are two kinds of attacks on this scheme: (1) anyone can forge some certain messages which to be sign and cannot detect by the signature verifier. (2) This scheme can’t resist the dishonest signer forgery attack by forging its own public key. After that, the paper proposed two new forward-secure multi-p...

It is shown that the throughput capacity of wireless ad hoc networks using omni-directional antennas (OMN networks) is significantly decreased with the increased number of nodes. One major reason lies in the interference caused by using omni-directional antennas, which just broadcast radio signal in all directions. Thus, a communication with multiple short-ranged hops is suggested in such netwo...

The Finite-Element-Analysis (FEA) is of major importance for the design and improvement of forging processes. In this field, FEA is traditionally used to predict die fill, residual stresses and forming forces. The intention of the work presented in this paper is the development of an advanced simulation model for the description of phase transformation processes in forging dies based on FEA. Th...

In the present investigation, an artificial neural network (ANN) model is developed to predict the isothermal hot forging behavior of AlCuMgPb aluminum alloy. The inputs of the ANN are deformation temperature, frictional factor, ram velocity and displacement whereas the forging force, barreling parameter and final shape are considered as the output variable. The developed feed-forward back-prop...

Ultra wideband (UWB) propagation is antenna-dependent, and multipath components experiencing specular diffraction or arriving at different angles have different shapes. To utilise the diversity of the multipath components, this study proposes a statistical model which incorporates directional parameters, such as elevation and azimuth angles by extending the IEEE802.15.3a model. Based on this mo...