An architecture and methodology for the design and development of Technical Information Systems

In order to meet demands in the context of Technical Information Systems (TIS) pertaining to reliability, extensibility, maintainability, etc., we have developed an architectural framework with accompanying methodological guidelines for designing such systems. With the framework, we aim at complex multiapplication information systems using a repository to share data among applications. The framework proposes to keep a strict separation between Man-Machine-Interface and Model data, and provides design and implementation support to do this effectively.\ud The framework and methodological guidelines have been developed in the context of the ESPRIT project IMPRESS. The project also provided for ldquotesting groundsrdquo in the form of a TIS for the Spanish Electricity company Iberdrola.\ud This work has been conducted within the ESPRIT project IMPRESS (Integrated, Multi-Paradigm, Reliable and Extensible Storage System), ESPRIT No. 635

GUERISON PAR L'HYDROGENE DE DEFAUTS RECOMBINANTS DANS LES COUCHES DE SILICIUM POLYCRISTALLIN RAD

Cet article présente les résultats d'études du rôle de l'incorporation d'hydrogène par plasma à 430 °C sur les caractéristiques électriques de photopiles préparées sur rubans RAD. Les performances des photopiles ont été caractérisées par le relevé de caractéristiques I (V) sous différents éclairements et de profils de photoréponse locale obtenus en mode LBIC ; la localisation de l'hydrogène ségrégé a été effectuée par autoradiographie sur des échantillons chargés en tritium. On met en évidence une neutralisation partielle des centres pièges dans le volume du matériau - corroborée par une forte ségrégation de l'hydrogène - et une passivation des interfaces, notamment des sous-joints de grains. Ces travaux montrent que l'incorporation d'hydrogène est envisageable pour améliorer les performances des photopiles RAD.Results of a study on the role of plasma hydrogenation at 430 °C on the electrical properties of solar cells made from RAD ribbons are presented. Solar cell performances were investigated on the basis of I (V) curves drawn at different illuminations and photoresponse scans obtained by an LBIC technique ; local hydrogen segregation was mapped by an autoradiography technique on tritium charged samples. A reduction of the activity of traps in the bulk - corroborated by a large hydrogen segregration effect - and a passivation of active boundaries, in particular sub-grain boundaries, were evidenced. It is concluded that hydrogenation may be foreseen as a means to improve the performances of RAD solar cells

An Architecture and Methodology for the Design and Development of Technical Information Systems

Abstract. In order to meet demands in the context of Technical Information Systems (TIS) pertaining to reliability, extensibility, maintainability, etc., we have developed an architectural framework with accompanying methodological guidelines for designing such systems. With the framework, we aim at complex multiapplication information systems using a repository to share data among applications. The framework proposes to keep a strict separation between Man-Machine-Interface and Model data, and provides design and implementation support to do this effectively. The framework and methodological guidelines have been developed in the context of the ESPRIT project IMPRESS. The project also provided for “testing grounds” in the form of a TIS for the Spanish Electricity company Iberdrola.

An architecture and methodology for the design and development of Technical Information Systems

In order to meet demands in the context of Technical Information Systems (TIS) pertaining to reliability, extensibility, maintainability, etc., we have developed an architectural framework with accompanying methodological guidelines for designing such systems. With the framework, we aim at complex multiapplication information systems using a repository to share data among applications. The framework proposes to keep a strict separation between Man-Machine-Interface and Model data, and provides design and implementation support to do this effectively. The framework and methodological guidelines have been developed in the context of the ESPRIT project IMPRESS. The project also provided for ldquotesting groundsrdquo in the form of a TIS for the Spanish Electricity company Iberdrola. This work has been conducted within the ESPRIT project IMPRESS (Integrated, Multi-Paradigm, Reliable and Extensible Storage System), ESPRIT No. 635

Passivation par l'hydrogène de défauts recombinants dans les photopiles réalisées sur rubans de silicium polycristallin RAD

Results of early hydrogen passivation studies of defects in polycrystalline silicon ribbons grown by the RAD process are presented. Hydrogen was incorporated in uncoated solar cells by means of a Kaufman ion source. It is shown that the solar cell characteristics, namely : the photocurrent density, the open-circuit voltage and the fill factor — are considerably improved whereas their distributions are narrowed These improvements are ascribed to an increase of the minority-carrier diffusion length in the bulk rather than to a reduction of the recombination velocity of minority-carriers at interfaces - grain or twin boundaries -; the bulk passivation goes along with an important reduction of the minority-carrier trap activity. Thus, the AM1 conversion efficiency of hydrogenpassivated RAD solar cells may be relatively high. The best cell thus treated had a conversion efficiency of 15.5 % (active area, 3 cm2 in size).Cet article présente les résultats d'une étude exploratoire de la passivation par l'hydrogène des défauts recombinants dans les rubans de silicium polycristallin élaborés par la méthode RAD. L'incorporation d'hydrogène a été effectuée sur des photopiles nues au moyen d'une source d'ions du type Kaufman. On montre que les caractéristiques globales des photopiles — photocourant, tension de circuit ouvert et facteur de forme — sont considérablement améliorées tandis que leurs distributions sont resserrées. Ces améliorations sont reliées à la réduction de la vitesse de recombinaison des porteurs minoritaires sur les interfaces du type joints de grains ou de mâcles et surtout, à l'augmentation de la longueur de diffusion dans les parties homogènes ; ce dernier effet est associé à une réduction importante de l'activité des centres pièges. Ainsi, le rendement de conversion, sous éclairement AM1, des photopiles RAD « passivées » à l'hydrogène peut être relativement élevé : la meilleure photopile ainsi traitée présente un rendement de 15,5 % (surface active, 3 cm 2)