Andrea Micangeli

Checking an integrated model of web accessibility and usability evaluation for disabled people

A combined objective-oriented and subjective-oriented method for evaluating accessibility and usability of web pages for students with disability was tested. The objective-oriented approach is devoted to verifying the conformity of interfaces to standard rules stated by national and international organizations responsible for web technology standardization, such as W3C. Conversely, the subjective-oriented approach allows assessing how the final users interact with the artificial system, accessing levels of user satisfaction based on personal factors and environmental barriers. Five kinds of measurements were applied as objective-oriented and subjective-oriented tests. Objective-oriented evaluations were performed on the Help Desk web page for students with disability, included in the website of a large Italian state university. Subjective-oriented tests were administered to 19 students labeled as disabled on the basis of their own declaration at the University enrolment: 13 students were tested by means of the SUMI test and six students by means of the ‘Cooperative evaluation’. Objective-oriented and subjective-oriented methods highlighted different and sometimes conflicting results. Both methods have pointed out much more consistency regarding levels of accessibility than of usability. Since usability is largely affected by individual differences in users own (dis)abilities, subjective-oriented measures underscored the fact that blind students encountered much more web surfing difficulties.

Efficient energy harvesting for Microbial Fuel Cell dedicated to Wireless Sensor Network

Microbial Fuel Cell (MFC) is novel technology for harvesting a fully sustainable zero emissions bioenergy that, by means of dedicated electronic circuits, suitably can be used for the proper functioning of a single Wireless Sensor Network (WSN) node. MFC is a bioreactor that transforms energy stored in chemical bonds of organic compounds into electrical energy. Low-power electronic devices allow now the design of electronic systems characterized by very low energy consumption. Accordingly, this allows the use of power sources based on energy harvesting techniques that involve clean renewable sources as MFC The first section of the paper introduces technological characteristics of the cell. The second one briefly examines the gap between electrical supplying of the cell and the energy requirements of WSN nodes. The design requires the usage of a step-up DC/DC converter, so the last part of the paper deals with the problems that occur when you want realize a system including a single MFC reactor for powering a single WSN node.

Exergy-Based Analysis of an Isolated Honduras Community

Environmental considerations are an essential part of any energy conversion assessment: especially in the analysis of natural reservations and protected areas, the concept of “environmental impact” has substantially evolved in the last decade, from an ex-post “assessment of ecological damage” to a complex, omni-comprehensive, but also pro-active and detailed, examination of the local and global implications of the interactions of anthropic processes with the biosphere. Evermore complete sets of quantitative measures of the interaction, called Environmental Indicators (El), have been developed with the intent of providing a sufficiently accurate and reliable decision support basis for planners and decision makers. There are though some intrinsic problems about this approach, more acutely felt in the analysis of natural systems: on the one hand, generality conflicts with specificity, and it is often difficult to connect a local El with a more global measure of environmental impact; on the other hand, several of the proposed Els are not completely satisfactory because they lack of a sound physical basis. Extended Exergy is an indicator that seems to overcome the above limitations: it is firmly rooted in thermodynamic principles and is articulated in such a way as to constitute a reliable quantitative measure of the total amount of primary resources consumed in a given conversion chain. The indicator is derived from a quite complex bookkeeping of the exergy fluxes of the system it is applied to, and makes use of two econometric coefficients for this quantification, which are external to the theory and must be calculated on the basis of proper labour and monetary statistics. In this paper, the method is applied to a community in northern Honduras, which is sufficiently remote and ill-connected with the rest of the Country to be considered in practice as an isolated system. The application of the Extended Exergy Accounting method to such a system constitutes an important benchmark, because the Labour fluxes are much more easily measured and the monetary circulation exerts a negligible influence on the evolution of the system.Copyright

Comparison Between Simea and Seneca Methods for Social Impact Analysis of Energy Systems

The SIMEA (Social Impact Method of Energy Analysis) and SENECA (Social and ENErgetic Change Analysis) are new methodologies to evaluate social impact, considering as environment not only the natural world, but also the economy structure, social organisation end cultural and historical aspects of a site. The aim of SIMEA is to consider in integrated way most of the possible effects on the environment (considering the definition of enlarged environment: nature, economy etc.) of the energy system and evaluate the social consequences on site where the energy system is installed of this effects as social impact. The SENECA method aims at evaluating the social change coming out from different energy choices within energy development projects in small rural communities. Through this method is possible to describe both an implemented and an implementing project using some indicators and a correlation, giving justification of the appropriate use of the chosen function. Aiming at the common scope of Social impact evaluation of energy systems, SIMEA and SENECA will use parameters that are chosen in different ways. In both cases the site is analysed from a social point of view starting from energetic changes. The surrounding areas are considered in different ways. For SIMEA it is only considered as parameter for the comparison to evaluate the local situation. SENECA method is based on a gravitational model, so that the surrounding areas are the gravitational field itself, and the migration flux, or the repulsive force, are based also on it.

SENECA method for a social evaluation of energy projects

The article suggests an experimental method for supporting evaluations of social consequences due to energetic projects in developing countries. It attempts to forecast possible side effects in the social-cultural texture of small rural communities.