140 research outputs found
Looking for the (missing) indicators of social sustainability - Evidence from sustainability standards in the coffee sector
Rising consumer interest for ethical and/or responsible products and the growing interweaving of social and environmental issues question the ability of scientific methods to correctly assess social impacts. To this day however, no consensus has yet been reached on relevant indicators to assess social impacts. In this article, we try to identify consistent indicators of social sustainability, based on the study and comparison of well-known sustainability standards currently used in the coffee sector (FLO, ESR, IMO, ETI, UTZ, Rainforest Alliance and Globalgap). The choice of relevant indicators is based on their realism and applicability, and on existing consensus among the standards on "minimal requirements" to certify sustainable practices in the coffee sector. Our main contributions to the debate on the choice of significant and relevant indicators are: to identify permanent features and areas of consensus between the different standards studied; and to question the definition of a socially sustainable product. ...French Abstract : L'intérêt grandissant des consommateurs pour les produits éthiques et/ou responsables et l'imbrication croissante des problématiques sociales et environnementales amènent à nous interroger sur la capacité des méthodes scientifiques actuelles à mesurer l'impact social. A ce jour, il n'existe pas de consensus autour d'indicateurs de durabilité sociale. Dans cet article, nous tentons d'identifier des indicateurs pertinents grâce à la comparaison de standards de durabilité communément utilisés dans le secteur du café (FLO, ESR, IMO, ETI, UTZ, Rainforest Alliance and Globalgap). Le choix de la pertinence des indicateurs est basé sur leur réalisme et leur applicabilité, ainsi que sur l'existence d'un consensus entre standards sur un " minimum requis " dans les cahiers des charges, pour la certification de pratiques socialement durables dans le secteur du café. Les contributions principales de ce papier sont : l'identification d'aires de consensus minimal entre les standards et une discussion de la durabilité sociale telle qu'elle est définie par ces standards.METHODS; SOCIAL LCA; SOCIAL STANDARDS; INDICATORS; FOOD SECTOR
Comparison of radiation damage in silicon induced by proton and neutron irradiation
The subject of radiation damage to Si detectors induced by 24-GeV/c protons and nuclear reactor neutrons has been studied. Detectors fabricated on single-crystal silicon enriched with various impurities have been tested. Significant differences in electrically active defects have been found between the various types of material. The results of the study suggest for the first time that the widely used nonionizing energy loss (NIEL) factors are insufficient for normalization of the electrically active damage in case of oxygen- and carbon-enriched silicon detectors. It has been found that a deliberate introduction of impurities into the semiconductor can affect the radiation hardness of silicon detectors. (16 refs)
Study of charge collection and noise in non-irradiated and irradiated silicon detectors
The large collection and noise were studied in non-irradiated and irradiated silicon detectors as a function of temperature (T), shaping time (0) and fluence , up to about 1,2 x 10(14) protons per cm2 for minimum-ionizing electrons yielded by a 106 Ru source. The noise of irradiated detectors is found to be dominted for short shaping times (¾50ns) by a series noise compo- nent, while for longer shaping times (80ns) a parallel noise component (correlated with the reverse current) prevails. For non-irradiated detectors, where the reverse current is three orders of magnetude smaller compared with irradiated detectors, the series noises dominates over the whole range of shaping times investigated (20-150ns). A signal degradation is observed for irradiated detectors. However, the signal ca be distinguished from noise, even after a fluence of about 1.2 x10(14) protons per cm2, at a temperature of 6øC and with a shaping time tipical of rge LHC inter-bunch crossing time (20-30ns). The measurements of the signal as a function of voltage shows that irradiated detectors depleted at 50% of the full depletion voltage can still provide a measurable signal-to-noise ratio
Pion-induced damage in silicon detectors
The damage induced by pions in silicon detectors is studied for positive and negative pions for fluence up to 10(14)cm-2 and 10(13) cm-2 respectively. Results on the energy dependence of the damage in the region of 65-330 MeV near to the resonance are presented. The change in detector characteristics such as leakage current, charge collection efficiency and effective impurity concentration including long-term annealing effects have been studied. Comparisons to neutron and proton-induced damage are presented and discussed
Bulk Damage Effects in Irradiated Silicon Detectors due to Clustered Divacancies
High resistivity silicon particle detectors will be used extensively in experiments at the future CERN Large Hadron Collider where the enormous particle fluences give rise to significant atomic displacement damage. A model has been developed to estimate the evolution of defect concentrations during irradiation and their electrical behaviour according to Shockley-Read-Hall (SRH) semiconductor statistics. The observed increases in leakage current and doping concentration changes can be described well after gamma irradiation but less well after fast neutron irradiation. A possible non-SRH mechanism is considered, based on the hypothesis of charge transfer between clustered divacancy defects in neutron damaged silicon detectors. This leads to a large enhancement over the SRH prediction for V2 acceptor state occupancy and carrier generation rate which may resolve the discrepancy
The ocean sampling day consortium
Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world’s oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits
Scanning of irradiated silicon detectors using particles and low energy protons
In a spectroscopic study of non-irradiated and proton-irradiated silicon diodes, the detectors were illuminated from the front side and from the rear side by various alpha particle sources (mainly ThC') and by monoenergetic protons with energies from 1.0 to 2.5~MeV. Their response characteristics have been studied as a function of the incoming particle energy and the applied bias voltage. The charge collection efficiency was determined as a function of fluenc
LHC1: a semiconductor pixel detector readout chip with internal, tunable delay providing a binary pattern of selected events
The Omega3/LHCl pixel detector readout chip comprises a matrix of 128 X 16 readout cells of 50 mu m X 500 mu m and peripheral functions with 4 distinct modes of initialization and operation, together more than 800 000 transistors. Each cell contains a complete chain of amplifier, discriminator with adjustable threshold and fast-OR output, a globally adjustable delay with local fine-tuning, coincidence logic and memory. Every cell can be individually addressed for electrical test and masking, First results have been obtained from electrical tests of a chip without detector as well as from source measurements, The electronic noise without detector is similar to 100 e(-) rms. The lowest threshold setting is close to 2000 e(-) and non-uniformity has been measured to be better than 450 e(-) rms at 5000 e(-) threshold. A timewalk of < 10 ns and a precision of < 6 ns rms on a delay of 2 mu s have been measured. The results may be improved by further optimization
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