Classification of Satellite Images by means of Fuzzy Rules generated by a Genetic Algorithm

The data acquired by Remote Sensing systems allow obtaining thematic maps of the earth's surface, by means of the registered image classification. This implies the identification and categorization of all pixels into land cover classes. Traditionally, methods based on statistical parameters have been widely used, although they show some disadvantages. Nevertheless, some authors indicate that those methods based on artificial intelligence, may be a good alternative. Thus, fuzzy classifiers, which are based on Fuzzy Logic, include additional information in the classification process through based-rule systems. In this work, we propose the use of a genetic algorithm (GA) to select the optimal and minimum set of fuzzy rules to classify remotely sensed images. Input information of GA has been obtained through the training space determined by two uncorrelated spectral bands (2D scatter diagrams), which has been irregularly divided by five linguistic terms defined in each band. The proposed methodology has been applied to Landsat-TM images and it has showed that this set of rules provides a higher accuracy level in the classification process

Emissions and economic costs of cycling compact fluorescent lamps with integrated ballasts

This paper proposes a way to quantify the emissions of mercury (Hg) and CO2 associated with the manufacture and operation of compact fluorescent lamps with integrated ballasts (CFLis), as well as the economic cost of using them under different operating cycles. The main purpose of this paper is to find simple criteria for reducing the polluting emissions under consideration and the economic cost of CFLi to a minimum. A lifetime model is proposed that allows the emissions and costs to be described as a function of degradation from turning CFLi on and their continuous operation. An idealized model of a CFLi is defined that combines characteristics stated by different manufacturers. In addition, two CFLi models representing poor-quality products are analyzed. It was found that the emissions and costs per unit of time of operation of the CFLi depend linearly on the number of times per unit of time it is turned on and the time of continuous operation. The optimal conditions (lowest emissions and costs) depend on the place of manufacture, the place of operation and the quality of the components of the lamp/ballast. Finally, it was also found that for each lamp, there are intervals when it is turned off during which emissions of pollutants and costs are identical regardless of how often the lamp is turned on or the time it remains on. For CO2 emissions, the lamp must be off up to 5 minutes; for the cost, up to 7 minutes and for Hg emissions, up to 43 minutes. It is advisable not to turn on a CFLi sooner than 43 minutes from the last time it was turned off.

Changes in the external costs of freight surface transport in Spain

This paper studies the external costs of surface freight transport in Spain and finds that a reduction occurred over the past 15 years. The analysis yields two conclusions: trucks have experienced a reduction in external costs, and rail has lower externalities. The external costs of road freight transport decrease between 1993 and 2007 (44%). The external costs of rail freight increase by 12%. During this period, the external costs of road freight related to climate increase by 16%, oppositely than those from air pollution and accidents (51 and 44%). The external costs of rail related to pollutant emissions and climate increase by 4% and 43%. Oppositely, the external costs related to accidents decrease by 27%. Road freight generates eight times the external costs of rail, 2.35 Euro cents per tonne kilometre in 2005 (5.6% accidents, 74.7% air pollution and 19.7% climate) vs. 0.28 (13.4% accidents, 53.9% air pollution and 32.7% climate).

Operational costs of A 13,000 solar home systems rural electrification programme

This paper presents an assessment and evaluation of the costs of operation and maintenance (O&M) in a real PV rural electrification (PVRE) programme, with the aim of characterizing its costs structure. Based on the extracted data of the 5-years operational costs of a private operator, the programme has been analyzed to take out the most relevant costs involved in the O&M phase as well as the comparative appraisal between the 3 main activities: installation, O&M and management. Through this study we try to answer to the new challenge of decentralized rural electrification based on larger programmes (with tens of thousands of SHSs) and longer maintenance and operation periods (at least 10 years).