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Coal fly ashes have been vitrified by melting with Na2O and CaO as fluxing additives. Adequate heat treatments on the fly ash derived glass produced attractive dark green glass-ceramics. These glass-ceramics exhibited fine-grained microstructures consisting of esseneite and nepheline crystals, with average size below 200 nm, homogeneously dispersed in a residual glassy matrix. Several properties, such as density, thermal expansion coefficient, bending strength, hardness and brittleness index were determined and the correlation microstructure-properties is discussed. The results suggest that these coal ash-based glass-ceramics have potential applications as structural materials or as cladding materials.

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In the recent past, multiple techniques and tools have been proposed and contributed to improve the distributed debugging functionalities, in several distinct aspects, such as handling the non-determinism, allowing cyclic interactive debugging of parallel programs, and providing more user-friendly interfaces. However, most of these tools are tied to a specific programming language and provide rigid graphical user interfaces. So they cannot easily adapt to support distinct abstraction levels or user interfaces. They also don't provide adequate support for cooperation with other tools in a software engineering environment. In this paper we discuss several dimensions which may contribute to develop more flexible distributed debuggers. We describe Fiddle, a distributed debugging tool which aims at overcoming some of the above limitations.

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This work presents a fast method to determine qualitatively the uniformity and the thickness of transparent or semitransparent thin films in the visible to near-infrared region. The method proposed is based on the information recorded by a colour scanner in the form of coloured regions, due to the constructive interferences caused by multibeam wavelength light sources as function of the film thickness and refractive index. The method is well applied in transparent films, where the uniformity cannot be seen by visual inspection. This paper shows that the results obtained for ZrO2 films are satisfactory enabling the application of this technique to determine the films uniformity in fast and cheap way.

In the recent past, multiple techniques and tools have been proposed and contributed to improve the distributed debugging functionalities, in several distinct aspects, such as handling the non-determinism, allowing cyclic interactive debugging of parallel programs, and providing more user-friendly interfaces. However, most of these tools are tied to a specific programming language and provide rigid graphical user interfaces. So they cannot easily adapt to support distinct abstraction levels or user interfaces. They also don’t provide adequate support for cooperation with other tools in a software engineering environment. In this paper we discuss several dimensions which may contribute to develop more flexible distributed debuggers. We describe Fiddle, a distributed debugging tool which aims at overcoming some of the above limitations.

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Water trees result from ac electrical aging of the polymeric insulation of medium and HV power cables in a humid or wet environment. As suggested by their name, they arise from penetration of water in the polymer. Visual observation with the help of an optical microscope shows tree (bush) type structures. This suggests that water trees might be fractal objects. Calculation of the fractal dimension from experimental samples may confirm the fractal characteristics and also give information on the damage caused to the polymer. In this work images of water trees taken under the optical microscope, dyed by methylene blue and etched for scanning electron microscopy (SEM), were studied in order to estimate the fractal dimension using a box-counting algorithm. The photographs, made using an optical microscope (scale of 100 mum), of the dyed samples were obtained from laboratory-aged low-density polyethylene (LDPE) specimens using accelerated techniques. Different field amplitude and frequency and also time of aging were used and the dimension values were compared. SEM images resulting from aged cross-linked polyethylene (XLPE) cables revealed a structure at a different scale (similar to 3 mum). Each photograph was analyzed to compare regions with and without water trees.

Water trees result from ac electrical aging of the polymeric insulation of medium and HV power cables in a humid or wet environment. As suggested by their name, they arise from penetration of water in the polymer. Visual observation with the help of an optical microscope shows tree (bush) type structures. This suggests that water trees might be fractal objects. Calculation of the fractal dimension from experimental samples may confirm the fractal characteristics and also give information on the damage caused to the polymer. In this work images of water trees taken under the optical microscope, dyed by methylene blue and etched for scanning electron microscopy (SEM), were studied in order to estimate the fractal dimension using a box-counting algorithm. The photographs, made using an optical microscope (scale of 100 mum), of the dyed samples were obtained from laboratory-aged low-density polyethylene (LDPE) specimens using accelerated techniques. Different field amplitude and frequency and also time of aging were used and the dimension values were compared. SEM images resulting from aged cross-linked polyethylene (XLPE) cables revealed a structure at a different scale (similar to 3 mum). Each photograph was analyzed to compare regions with and without water trees.

The socio-economic subsystem encompassing fisheries may be defined as including not only the harvesting sector but also several related activities occurring both upstream (shipbuilding, gear manufacture) and downstream (processing, distribution and trade). But these closely interrelated economic activities can also be set within a much broader system which would include the ecological, institutional and political influences which frame economic behaviour. The value of this broader conceptualisation is that it treats fisheries not as an isolated and independent economic activity but as part of a more holistic and complex system. This broader perspective is of particular significance when attempting to examine the concept of regional dependence. The socio-economic subsystem for fisheries is dominated by small and medium sized enterprises (SMEs). And Peniche emerges as one of Portugal’s most important fishing ports whether measured in terms of the volume of landings or the total numbers of fishermen. It also has one of the highest levels of fisheries dependence of all coastal municipalities in Portugal with over 20% of its workforce currently engaged in fisheries related employment, faces a daunting and uncertain future. The social fabric of fisheries dependent communities also suffers serious damage; once again, the technocratic approach to management has no solutions to offer. It is essential, therefore, to turn away from the existing approach and to develop instead new forms of intervention; in short, to provide a new vision. This implies change not only to the policy process but also in the attitudes of the social actors and in the preoccupations of fisheries related research. An integrated approach is required based on participative action and the development of an integrated information network.

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Large area thin film position sensitive detectors based on amorphous silicon technology have been prepared on polyimide substrates using the conventional plasma-enhanced chemical vapour deposition. The sensors have been characterized by spectral response, light intensity dependence and linearity measurements in a bent state in order to evaluate the properties in real working conditions. The obtained one-dimensional (1D) position sensors with 10 mm width and 20 mm length present a non-linearity of ±1% which are comparable to the ones produced on glass substrates.

{We prove, under certain regularity assumptions on the coefficients, that tangent processes (namely semimartingales d xi(tau) = a dx(tau) + b d tau where a is an antisymmetric matrix) generate flows on the classical Wiener space. Main applications of the result can be found in the study of the geometry of path spaces. (C) 1999 Academic Press.}

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As a Norwegian sociologist pointed out recently at the Encontro Internacional de Vilamoura on Fishing, “the fisheries management is the management of people, not fish" This statement may surprise many specialists, but it puts once again a series of questions and problems in their true place: society, social relationships, individuals. It is necessary to adopt a new attitude, a new type of intervention, a new vision, which may mean “community management”, a system of co-management, new models of business organisation and consumer behaviour. Towards this end, sociology can and should contribute with its analytical instruments, with its set of scientific reflections and controversies, to the enrichment of the knowledge about a complex reality in profound change, such as that of the socio-economic fisheries system.