Experimental investigation on consolidation behavior of mud: Subreport 1. Methodology study

Due to the complex nature of mud consolidation within harbours, a robust and accurate guideline to evaluate the nautical depth is still under debate. Besides, alternative dredging techniques (e.g. mud conditioning/fluidising) have proven to be an applicable method to reduce dredging costs in a number of harbours. Yet, before one can define new criteria for nautical depth or implement new dredging techniques, a deeper understanding of the temporal evolution of rheological, mechanical and biological characteristics of mud is needed. In this study, we aim to improve the understanding of the rheological properties of consolidating mud by comparing the consolidation process of mud from 5 different locations namely the harbours of Zeebrugge (ZB) and Deurganckdok (DG) in Belgium, the harbours of Rotterdam (RO) and Ijmuiden (IJ) in the Netherlands and the Emden (EM) harbour in Germany. The main objectives of this project are to examine the effect of the consolidation process on the mechanical, rheological and biological characteristics of mud as well as to explain the differences in consolidation processes between muds from different origins.This sub-report describes the properties of different mud types used for the experiments as well as the experimental setup. The experimental setup includes a detailed description of the governing parameters, experimental design and measurement techniques conducted on two different consolidation columns, small and large

Performance of an autonomous energy harvesting wireless sensor

While complex autonomic self-organising systems have received much attention, simple autonomous systems are also needed for remote sensing applications, as well as for the Internet of Things. Such autonomous stand-alone unattended devices may not have access to reliable sources of mains power, and will have to harvest energy locally from ambient sources such as vibrations, heat or light. However energy leakage will also be a problem. This paper proposes a mathematical model to analyse the performance of such systems in the presence of a random source of energy, as well as a random source of data. The equilibrium between random energy, random data and random leakage results in an interesting performance analysis of these small but ubiquitous systems as a whole. A discussion is also provided about the effect of transmission errors