Abstract
This paper presents a new generation of man portable acoustic navigation buoys. The aim of these buoys is to facilitate the deployment of an underwater acoustic positioning system for the operation of Autonomous Underwater Vehicles. Each buoy includes only the vital modules required for the most typical schemes of underwater acoustic navigation, packed in a small but dynamically stable platform for one day long operations in coastal waters. We will present an overview of the systems hardware and electronics, and also the key features of the deployment and operation of the beacons.

Abstract
The energy consumption in the world continues to increase and this fact contributes to rise pollution levels, environmental degradation and global greenhouse emissions. The construction sector is responsible for significant impacts on the environment as it consumes a lot of resources and also produces a lot of waste. One of the main objectives of the green construction is to reduce the environmental impacts by conserving and using resources more efficiently. This type of construction tends to apply natural raw materials. Tabique is a traditional Portuguese building technique applied until 20th century that use earth and wood as construction materials. This old buildings have high durability that requires maintenance and rehabilitation interventions. In this context, the aim of this study is to evaluate the environmental impact of tabique wall. The life cycle analysis is the tool used for the sustainability evaluation and it is carried out according to international standards ISO 14040/44. The adopted functional unit for these materials is the mass of the material required to provide a thermal resistance of 1 m2ºC/W. The calculation of the impacts is done with GaBi software and the CML 2001 impact category is used to define the Global Warming Potential of the study. The results revealed that most significant component of environmental impact of the tabique wall cocerning the category GWP is related with extraction of raw materials process and landfill.

Abstract

Abstract
There is growing recognition that decarbonisation of existing uses of electricity is only 'part of the story' and that closer attention needs to be given to demand for energy in heating or cooling and in transport, and to all the energy vectors and infrastructures that supply the end-use demand. In this respect, concepts such as 'multi-energy systems' (MES) have been put forward and are gaining increasing momentum, with the aim of identifying how multiple energy systems that have been traditionally operated, planned and regulated in independent silos can be integrated to improve their collective technical, economic, and environmental performance. This paper addresses the need for modelling of MES which is capable of assessing interactions between different sectors and the energy vectors they are concerned with, so as to bring out the benefits and potential unforeseen or undesired drawbacks arising from energy systems integration. Drivers for MES modelling and the needs of different users of models are discussed, along with some of the practicalities of such modelling, including the choices to be made in respect of spatial and temporal dimensions, what these models might be used to quantify, and how they may be framed mathematically. Examples of existing MES models and tools and their capabilities, as well as of studies in which such models have been used in the authors' own research, are provided to illustrate the general concepts discussed. Finally, challenges, opportunities and recommendations are summarised for the engagement of modellers in developing a new range of analytical capabilities that are needed to deal with the complexity of MES.

Abstract

Abstract