96 research outputs found
40 Gbps Access for Metro networks: Implications in terms of Sustainability and Innovation from an LCA Perspective
In this work, the implications of new technologies, more specifically the new
optical FTTH technologies, are studied both from the functional and
non-functional perspectives. In particular, some direct impacts are listed in
the form of abandoning non-functional technologies, such as micro-registration,
which would be implicitly required for having a functioning operation before
arrival the new high-bandwidth access technologies. It is shown that such
abandonment of non-functional best practices, which are mainly at the
management level of ICT, immediately results in additional consumption and
environmental footprint, and also there is a chance that some other new
innovations might be 'missed.' Therefore, unconstrained deployment of these
access technologies is not aligned with a possible sustainable ICT picture,
except if they are regulated. An approach to pricing the best practices,
including both functional and non-functional technologies, is proposed in order
to develop a regulation and policy framework for a sustainable broadband
access.Comment: 10 pages, 6 Tables, 1 Figure. Accepted to be presented at the
ICT4S'15 Conferenc
Évolution du protocole GTP dans un contexte de VPN et de mobilité-IP
Définitions et concepts de base -- Éléments de la problématique -- Objectifs de la recherche -- Plan du mémoire -- Analyse du protocole GTP -- Réseau mobile IP basé sur MPLS -- Mobilité basée sur les technologies VPN -- Gestion de mobilité tout-IP -- Concepts complémentaires de mobilité et d'intégration VPN -- Améliorations proposées au protocole GTP -- Fondements des améliorations proposées -- Évolution proposée de GTP -- Le diagramme de séquence des messages -- Résultats expérimentaux et analytiques -- Environnement de simulation -- Plan d'expérience -- Expérimentation et analyse des résultats -- Conclusion -- synthèse des travaux -- Limitations principales -- Indications pour des recherches futures
Challenges and complexities in application of LCA approaches in the case of ICT for a sustainable future
In this work, three of many ICT-specific challenges of LCA are discussed.
First, the inconsistency versus uncertainty is reviewed with regard to the
meta-technological nature of ICT. As an example, the semiconductor technologies
are used to highlight the complexities especially with respect to energy and
water consumption. The need for specific representations and metric to
separately assess products and technologies is discussed. It is highlighted
that applying product-oriented approaches would result in abandoning or
disfavoring of new technologies that could otherwise help toward a better
world. Second, several believed-untouchable hot spots are highlighted to
emphasize on their importance and footprint. The list includes, but not limited
to, i) User Computer-Interfaces (UCIs), especially screens and displays, ii)
Network-Computer Interlaces (NCIs), such as electronic and optical ports, and
iii) electricity power interfaces. In addition, considering cross-regional
social and economic impacts, and also taking into account the marketing nature
of the need for many ICT's product and services in both forms of hardware and
software, the complexity of End of Life (EoL) stage of ICT products,
technologies, and services is explored. Finally, the impact of smart management
and intelligence, and in general software, in ICT solutions and products is
highlighted. In particular, it is observed that, even using the same
technology, the significance of software could be highly variable depending on
the level of intelligence and awareness deployed. With examples from an
interconnected network of data centers managed using Dynamic Voltage and
Frequency Scaling (DVFS) technology and smart cooling systems, it is shown that
the unadjusted assessments could be highly uncertain, and even inconsistent, in
calculating the management component's significance on the ICT impacts.Comment: 10 pages. Preprint/Accepted of a paper submitted to the ICT4S
Conferenc
Gas sensing with SU-8 whispering gallery mode resonators
We present an optical gas sensor using SU-8 microdisk whispering gallery mode resonators. Sensitivities were measured for different vapor phases: water, toluene, limonene and valeric acid. The highest reported sensitivity is 18.98 pm/ppm
All-polymer whispering gallery mode resonators for gas sensing
Sensitivity of polymeric microdisks is evaluated for selected compounds in their vapor phase such as humidity, isopropanol, toluene, limonene, 1-butanol, and pentanoic acid (valeric acid). Among these compounds, pentanoic acid exhibits the highest sensitivity (23 pm/ppm) with a limit of detection estimated to be around 0.6 ppm. We are interested in the contribution of the geometry deformation due to polymer swelling on the sensitivity as it may be engineered to improve performance of gas sensing devices. Experimental observations show a trend where sensitivity to humidity increased with the ratio of the undercut over the radius of the microcavity
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