20 research outputs found

    Decarbonizing bulk shipping combining ship design and alternative power

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    The Sixth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) stresses the urgency to rapidly reduce global Greenhouse Gas (GHG) emissions to contain global warming. The main focus in the design of bulk vessels for several decades has been maximizing cargo-carrying capacity at the lowest build cost. Reduction in energy consumption and emissions, if achieved at all, was heavily limited by the main design focus. This paper decarbonizes bulk shipping by combining ship design and alternative power. The results indicate: First, building more slender bulk vessels that are powered with wind-assisted propulsion reduces fuel consumption and GHG emissions by around 25% at an abatement cost of less than Zero, i.e., free of charge; Second, when combining slender hull and wind-assisted propulsion with Zero-carbon fuels, a 100% GHG reduction comes at an abatement cost of 328 USD per ton of CO2, which is still significantly less than the 459 USD per ton of CO2 with Zero-carbon fuels only.publishedVersio

    Wise use of renewable energy in transport

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    The transport sector accounts for around 25 % of global energy use, considering both fuel production and consumption. To mitigate climate change, a fast decarbonization of transport is therefore often seen as a necessity, as advocated by the International Energy Agency in its Net Zero by 2050 scenario. In contrast, Shell's Sky scenario envisages Net Zero by 2070 by first picking the lowest hanging fruits within all sectors, and hence a much slower de-carbonization of the transport sector. We investigate how renewables, a scarce resource over the next decades, could be used most wisely within the transport sector or alternatively within the energy sector. Our results stress that priority up to 2050 should be: First, to use new renewable energy to replace coal fired electricity production to nearly decarbonize the electricity grid; Second, to gradually electrify road transport; Third, continued use of fossil fuel in shipping and aviation.publishedVersio

    Un ancien lac au pied de l’<i>oppidum</i> de Gergovie (Puy-de-Dôme) : interactions sociétés-milieux dans le bassin de Sarliève à l’Holocène

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    International audienceZiel der seit 1997 im Becken von Sarliève, am Fuß des Oppidums von Gergovia (Puy-de-Dôme) durchgeführten Studien ist es, die wechselseitigen Beziehungen zwischen Mensch und Umwelt über einen langen Zeitraum aus einem systemischen und interdisziplinären Blickwinkel zu betrachten. Die Untersuchungen beziehen sich auf ein Niederschlagsgebiet mittlerer Größe in einer Region von eminenter geschichtlicher Bedeutung. Drei Untersuchungsachsen wurden definiert: •die Analyse der Entwicklung der Umwelt im Bereich dieses Niederschlagsgebietes in Hinsicht auf seine unterschiedlichen biophysikalischen Komponenten; •die Analyse der Geschichte der Flächennutzung und der Bewirtschaftung des Beckens durch die sich ablösenden Bevölkerungsgruppen; •die Analyse der durch den Menschen hervorgerufenen Umweltbelastung (Pflanzendecke, hydrosedimentäre Kräfte). Die Ergebnisse dieser Forschungen liefern die Elemente für die Erstellung eines sozialökologischen Modells, das das von 1970-1980 für die Grande Limagne ausgearbeitete Modell ablöst. Eine Abfolge von Agrarzyklen ist deutlich erkennbar. Diese stehen im Zusammenhang mit Phasen starker menschlicher Einflussnahme, die für das Mittelneolithikum, die Früh-und Spätbronzezeit, die ältere Eisenzeit, die späte Latène-und frühe Kaiserzeit, das Mittelalter und die Neuzeit erkannt wurden. Diese Zyklen sind eng verknüpft nicht nur mit der Entwicklung der Pflanzen und der Sedimentierungsdynamik, sondern auch mit den Schwankungen des Wasserstandes. In der Bronzezeit und im Mittelalter werden Transgressionsphasen mit besonders umfangreichen und einengenden Auswirkungen nachgewiesen. Der niedrige Pegel des Paläosees in der jüngeren Eisenzeit und der frühen Kaiserzeit begünstigt dagegen die Besiedlung der Uferregionen und sogar der Sohle des Beckens, das um die Zeitenwende durch ein Entwässerungssystem vollständig trocken gelegt wird. In der ersten Hälfte des 2. Jh. v. Chr. wird mit der starken Intensivierung der Siedlungstätigkeit in sämtlichen topographischen Kontexten eine deutliche quantitative Schwelle überschritten. Die Ergebnisse der archäologischen und paläoökologischen Untersuchungen lassen die methodische Erschließung der fruchtbarsten Böden im Zusammenhang mit einem stetigen wirtschaftlichen und demographischen Wachstum erkennen, das mit dem Bau großer als “zentrale Plätze“ interpretierter Siedlungen (La Grande Borne in Aulnat, Oppida von Corent, Gergovia und Gondole) zusammenfällt. In den ersten beiden Jahrhunderten unseres Zeitalters setzt sich diese Tendenz im Rahmen der Ökonomie der villae, die sich infolge der Gründung von Augustonemetum, der neuen Hauptstadt der avernischen civitas herausbildet, mit der von den Geländeformen unabhängigen Ausweitung der landwirtschaftlichen Nutzung auf das gesamte Becken fort. In der Spätantike und im frühen Mittelalter gewinnt der Sumpf in einem feuchteren Klima wieder an Boden, besonders durch die grundlegenden Veränderungen in der Art und Weise das Gebiet zu nutzen. Die mittelalterlichen Texte und die neuzeitliche Ikonographie bezeugen die Existenz eines Sees, der zu Beginn des 17. Jh. schließlich endgültig trockengelegt wird.The aim of the researches conducted since 1997 in the basin of Sarliève, at the foot of the oppidum of Gergovia (Puy-de-Dôme), is to detect in a systemic and interdisciplinary perspective the longlasting interactions societies/environment on the scale of a mediumsized basin located in a major area from an historical point of view. Three axes have been defined : * the characterization of the evolution of the environment on the scale of the basin inside its various biophysical components ; * the characterization of the history of land occcupation and of the exploitation of environment by successive populations settled in the basin ; * the characterization of the impact of human pressure on the environment (plant cover, hydro-sedimentary dynamics). Results provide elements of a new socioenvironmental model after the model completed in Limagne in the 1970'-1980'. A succession of land cycles has been detected and connected to phases of strong human pressure identified for Middle Neolithic, Early and Late Bronze Age, Early Iron Age, Early Empire, Middle Age and Modern period. These cycles are tightly connected with vegetation evolution and sedimentary dynamics but also with vertical variations of the lake level. Some phases of encroachment, particularly wide and constraining, have been revealed for Bronze Age and Middle Age. The low level of the lake during the Late Iron Age and the Early Empire in the other hand is favourable to the occupation of the edges and even at the bottom of the basin which is entirely drained due to a draining system at the turn of our era. A definite quantitative step, during the first half of the 2nd century BC, is represented by the high densification of the populated area in all kinds of physical units. Archaeological and environmental datas reveal a methodic exploitation of the most fertile lands in a context of continuous economic and demographic environment which coincides with the birth of towns identified as "central places" (such as la Grande Borne at Aulnat and the oppida of Corent at Veyre-Monton, Gergovia at La Roche-Blanche and Gondole at Le Cendre). This tendency goes on during the first two centuries AD, with the generalization of agrosystem to the whole basin, for any kind of relief, in the context of economic estates growing since the foundation of Augustonemetum, the new capital of the Arverni. The return of marsh in Late Antiquity and Early Middle Age is due to a more humid climate and to deep changes in the methods of environmental management. A real lake is attested by medieval sources and modern iconography and is definitely dried out at the beginning of the 17th century.Les recherches conduites depuis 1997 dans le bassin de Sarliève, au pied de l'oppidum de Gergovie (Puy-de-Dôme), visent à appréhender, dans une perspective systémique et interdisciplinaire, les interactions sociétés-milieux dans la longue durée, à l'échelle d'un bassin-versant de taille moyenne localisé dans une zone de première importance sur le plan historique. Trois axes de recherche ont été définis : * la caractérisation de l'évolution du milieu à l'échelle du bassin-versant dans ses différentes composantes biophysiques ; * la caractérisation de l'histoire de l'occupation du sol et de l'exploitation du milieu par les populations successives établies dans le bassin ; * la caractérisation de l'impact de la pression anthropique sur le milieu (couverture végétale, dynamiques hydrosédimentaires). Les résultats obtenus fournissent les éléments d'un modèle socio-environnemental qui renouvelle celui élaboré pour la Grande Limagne dans les années 1970-1980. Une succession de cycles agraires est clairement mise en évidence. Ceux-ci sont liés à des phases de forte pression humaine identifiées au Néolithique moyen, au Bronze ancien, au Bronze final, au premier âge du Fer, à La Tène finale, au Haut-Empire, au Moyen Âge et à l'époque moderne. Ces cycles sont étroitement corrélés avec l'évolution de la végétation et la dynamique sédimentaire, mais également avec les variations verticales du plan d'eau. Des phases de transgression particulièrement amples et contraignantes sont mises en évidence durant l'âge du Bronze et le Moyen Âge. Le bas niveau du paléolac durant le second âge du Fer et le Haut-Empire est, en revanche, propice à l'occupation des bordures et même du fond de la cuvette, qui est complètement asséchée grâce à un système de drainage aménagé aux environs du changement d'ère. Un seuil quantitatif très net est franchi dans la première moitié du IIe s. av. J.-C., avec la forte densification de l'habitat dans tous les types d'unités physiques. Les données archéologiques et paléoenvironnementales traduisent la mise en valeur méthodique des sols les plus fertiles, dans un contexte de croissance économique et démographique continue qui coïncide avec l'apparition de vastes agglomérations interprétées comme des " places centrales " (agglomération de la Grande Borne à Aulnat, oppida de Corent à Veyre-Monton, Gergovie à La Roche-Blanche et Gondole au Cendre). Cette tendance se poursuit durant les deux premiers siècles de notre ère, avec la généralisation de l'agrosystème à l'ensemble du bassin, quels que soient les types de reliefs, dans le cadre de l'économie domaniale qui se développe à la suite de la fondation d'Augustonemetum, nouvelle capitale de la cité arverne. La fin de l'Antiquité et le haut Moyen Âge voient le retour du marais à la faveur d'un climat plus humide et, surtout, de profonds changements dans les modalités de gestion du milieu. Un véritable lac est attesté par les textes médiévaux et par l'iconographie moderne. Il est définitivement asséché au début du XVIIe s

    Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study

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    Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation

    Cluster Dynamics and Innovation

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    The present paper presents the concept of cluster, what they are, which benefits they offer, the various types of clusters, the main elements forming a duster, and a tentative mode! for explaining the dynamics of dusters and innovation. Clusters are "geographically proximate group of interconnected companies and associated institutions in a particular field, linked b commonalities and complementarities" (Porter, 1998:199). Clusters' most known and/or perceived benefits are the positive effects of agglomeration, such as the proximity between firms facilitating collaboration and triggering rivalry amon!l companies, a signiflcant R&D environment and a high degree of lnteraction and knowledge sharing to sustain a culture o entrepreneurship and innovation. Seeking to understand how industrial dusters can foster innovation and vice versa, the perspective taken in the presenl paper is the innovation system view on clusters (gupta et al., 2008). The four main elements definlng a cluster are the cluste1 members, their interactian, the knowledge and innovation generated, and the economical impact of the cluster activities. tro understand the dynamics of clusters, a conceptual mode! is proposed, highlighting the main forces driving an industrlal cluster and its underlying mechanism. Central to the duster are innovations, firm growth and formation, and duster attractiveness, which are supported by market growth, business and social interactions, entrepreneurship, competence and tacit knowledge, knowledge sharing, education and R&D. These forces are then put together in a system driven by five mechanisms: cooperation and riva/ry, interactions, knowledge development, technology development, and market 'development. The mode! is tested on a maritime duster perceived as very innovative. This mode! can be used for: 1) illustrating the interrelatedness of each duster element, and show their relative importance, 2) scenario planning, to predic1 negative effects of particular decisions, or events, as well as to point out the necessity of specific ameliorations, 3) monitoring performance, by providing a sort of check-list to develop a duster and assess performance over time. However, there are several limitations to the mode!, and the fact that it does not take into account external obstades not necessaril related to the cluster's drivers. These can be: - Culture, such as firms' resistance to change, reluctance to knowledge sharing - External forces, like constraining regulations - Financial constrains: such as high costs of applying new technology - Cluster's resources, such as available labour force To improve the usefulness of the proposed mode!, further development could focus on testing it on a series of othe1 industrial clusters, correct it and develop it further. Systematise it and improve its exploitability, by introducing weight to each driver and enable performance measurement and benchmarking among dusters.Innovation in Global Maritime ProductionpublishedVersio

    Batteries in offshore support vessels – Pollution, climate impact and economics

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    This paper assesses the pros and the cons of installing batteries on offshore support vessels. These vessels are specially designed to provide services to oil and gas operations, such as anchor handling, supply and subsea operations. They have multiple engines and advanced dynamic positioning systems to ensure that they can perform their duties with high reliability at nearly any sea state. Combined with high safety requirements, this has resulted in general operational patterns with vessels running multiple combustion engines even at calm water conditions. For emissions, low engine loads yield high emissions of exhaust gases such as nitrogen oxides (NOx) and aerosols such as black carbon (BC), due to less favorable combustion conditions. The high span for these vessels between low loads and high, and their great need for potential power at short notice, motivate our examination of hybrid setups with electric: the vessel segment should be more favorable than many. We find that combining batteries with combustion engines reduces local pollution and climate impact, while the economics with current battery cost and fuel prices is good enough for new vessels, but not good enough for retrofits

    Decarbonizing Maritime Transport: The Importance of Engine Technology and Regulations for LNG to serve as a Transition Fuel

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    Current Greenhous gas emissions (GHG) from maritime transport represent around 3% of global anthropogenic GHG emissions and will have to be cut in half by 2050 to meet Paris agreement goals. Liquefied natural gas (LNG) is by many seen as a potential transition fuel for decarbonizing shipping. Its favorable hydrogen to carbon ratio compared to diesel (marine gas oil, MGO) or bunker fuel (heavy fuel oil, HFO) translates directly into lower carbon emissions per kilowatt produced. However, these gains may be nullified once one includes the higher Well-to-tank emissions (WTT) of the LNG supply chain and the vessel’s un-combusted methane slip (CH4) from its combustion engine. Previous studies have tended to focus either on greenhouse gas emissions from LNG in a Well-to-wake (WTW) perspective, or on alternative engine technologies and their impact on the vessel’s Tank-to-wake emissions (TTW). This study investigates under what conditions LNG can serve as a transition fuel in the decarbonization of maritime transport, while ensuring the lowest possible additional global warming impact. Transition refers to the process of moving away from fossil fuels towards new and low carbon fuels and engine technologies. Our results show: First, the importance of applying appropriate engine technologies to maximize GHG reductions; Second, that applying best engine technologies is not economically profitable; Third, how regulations could be amended to reward best engine technologies. Importantly, while the GHG reduction of LNG even with best engine technology (dual fuel diesel engine) are limited, ships with these engines can with economically modest modification switch to ammonia produced with renewable energy when it becomes available in sufficient amounts.This study has been financially supported by the Norwegian Research Council project (Norges Forskningsråd) SFI Smart Maritime project number 237917.publishedVersio

    Virtualization of food supply chains with the internet of things

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    -Internet technologies allow supply chains using virtualizations dynamically in operational management processes. This will improve support for food companies in dealing with perishable products, unpredictable supply variations and stringent food safety and sustainability requirements. Virtualization enables supply chain actors to monitor, control, plan and optimize business processes remotely and in real-time through the Internet, based on virtual objects instead of observation on-site. This paper analyses the concept of virtual food supply chains from an Internet of Things perspective and proposes an architecture to implement enabling information systems. As a proof of concept, the architecture is applied to a case study of a fish supply chain. These developments are expected to establish a basis for virtual supply chain optimization, simulation and decision support based on on-line operational data. In the Internet of Things food supply chains can become self-adaptive systems in which smart objects operate, decide and learn autonomously

    State-of-the-art technologies, measures, and potential for reducing GHG emissions from shipping – A review

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    CO2 emissions from maritime transport represent around 3% of total annual anthropogenic greenhouse gas (GHG) emissions. These emissions are assumed to increase by 150–250% in 2050 in business-as-usual scenarios with a tripling of world trade, while achieving a 1.5– 2 C climate target requires net zero GHG emissions across all economic sectors. Consequentially, the maritime sector is facing the challenge to significantly reduce its GHG emissions as contribution to the international ambition to limit the effects of climate change. This article presents the results of a review of around 150 studies, to provide a comprehensive overview of the CO2 emissions reduction potentials and measures published in literature. It aims to identify the most promising areas, i.e. technologies and operational practices, and quantify the combined mitigation potential. Results show a significant variation in reported CO2 reduction potentials across reviewed studies. In addition, no single measure is sufficient to achieve meaningful GHG reductions. Emissions can be reduced by more than 75%, based on current technologies and by 2050, through a combination of measures if policies and regulations are focused on achieving these reductions. In terms of emissions per freight unit transported, it is possible to reduce emissions by a factor of 4–6

    Decarbonizing Maritime Transport: The Importance of Engine Technology and Regulations for LNG to serve as a Transition Fuel

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    Current Greenhous gas emissions (GHG) from maritime transport represent around 3% of global anthropogenic GHG emissions and will have to be cut in half by 2050 to meet Paris agreement goals. Liquefied natural gas (LNG) is by many seen as a potential transition fuel for decarbonizing shipping. Its favorable hydrogen to carbon ratio compared to diesel (marine gas oil, MGO) or bunker fuel (heavy fuel oil, HFO) translates directly into lower carbon emissions per kilowatt produced. However, these gains may be nullified once one includes the higher Well-to-tank emissions (WTT) of the LNG supply chain and the vessel’s un-combusted methane slip (CH4) from its combustion engine. Previous studies have tended to focus either on greenhouse gas emissions from LNG in a Well-to-wake (WTW) perspective, or on alternative engine technologies and their impact on the vessel’s Tank-to-wake emissions (TTW). This study investigates under what conditions LNG can serve as a transition fuel in the decarbonization of maritime transport, while ensuring the lowest possible additional global warming impact. Transition refers to the process of moving away from fossil fuels towards new and low carbon fuels and engine technologies. Our results show: First, the importance of applying appropriate engine technologies to maximize GHG reductions; Second, that applying best engine technologies is not economically profitable; Third, how regulations could be amended to reward best engine technologies. Importantly, while the GHG reduction of LNG even with best engine technology (dual fuel diesel engine) are limited, ships with these engines can with economically modest modification switch to ammonia produced with renewable energy when it becomes available in sufficient amounts
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