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Solar power appears to be one of the most promising resources to meet the medium and long term renewable energy targets. The integration of large amounts of photovoltaic (PV) generation into distribution networks faces some limitations due to the network constraints. The PV community became well aware of these limitations in the last years. While first solutions have been pointed out mainly for large installations connected to the medium voltage network, the specificities of low voltage networks are still not fully understood. This paper aims at explaining the challenges associated to the planning and operation of low voltage network with high PV penetration. The actual impact of PV infeed is quantified on the basis of real and accurate network, load and generation data. Results from unsymmetrical load-flow computations are presented and the implementation of reactive power-based voltage control is shortly discussed. 26th European Photovoltaic Solar Energy Conference and Exhibition; 4469-4478

Given the highly climate-sensitive character of agricultural production, climate change has obvious and important ramifications for agricultural commercialisation, which in turn has a bearing on poverty, gender empowerment, and food and nutrition security. The nature and extent of climate change implications for agricultural commercialisation will depend on: the magnitude of the climate impacts that farmers have to deal with; and, the extent to which sustainable intensification processes can be pursued in ways which strengthen, rather than weaken, adaptive capacity and resilience in the face of climate change. This brief provides a summary of a longer working paper, which offers a review of recent literature on the implications of climate change for agricultural commercialisation and APRA’s research in this area.

The importance of wind energy has progressed rapidly in the last years. Although Horizontal Axis Wind Turbines (HAWT) are most well-spread, there is an increasing interest in Vertical Axis Wind Turbines (VAWT), especially in the H-Darrieus concept, as these rotors are omni-directional and affordable. However, the physics of these rotors is more complex; they can only be analyzed using transient CFD simulations. Due to the finite aspect ratio of the rotors, a wingtip vortex is created, which generates losses. Optimizing the wingtip geometry could be advantageous for increasing the efficiency of the rotors: this can only be achieved with three-dimensional turbulent transient simulations. For the optimization of winglets, the whole process (mesh generation, CFD computation, post-processing) has to be automated. This is achieved using the OPtimization Algorithm Library++ (OPAL++), a custom C++ code for the description of blended and canted winglets, coupled with a CD-Adapco StarCCM+ JAVA script for the automatization of the mesh generation and CFD computations. To check the viability of the present concept, two parameters have been varied in the simulations. As shown in what follows, an efficient automatic optimization of wind turbine wingtips can be implemented in this manner.

Increasing agricultural productivity is one of the most important aims of modern biotechnology. One way to enhance the productivity of crop species is to enhance the efficiency of photosynthesis. In C3 plants the oxygenase activity of Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) limits the photosynthetic efficiency. The green microalgae Chlamydomonas reinhardtii has evolved a CO2 concentration mechanism (CCM) by increasing the CO2 concentration in the chloroplast stroma where RuBisCO is located. Four independent transgenic tobacco genotypes (LA, LB, C1 and C3) were generated producing the low CO2-inducible protein A and B (LCIA and LCIB) or the carbonic anhydrases I and III (CAH1 and CAH3) from C. reinhardtii CCM in the envelope, stroma, intermembrane space or thylakoid lumen of tobacco chloroplasts, respectively. All four recombinant proteins were active in planta, which had a substantial impact on carbon and nitrogen metabolism. Increasing the CO2 concentration near RuBisCO resulted in an enhanced rate of photosynthesis (by up to 15%), efficiency of photosystem II (by up to 18%) and chlorophyll content (by up to 19%). Although to differing extents, all four transgenic genotypes grew faster than wild-type plants, produced more shoot biomass (up to 45% more fresh weight or 38% more dry weight in the LA lines) and accumulated more photosynthetic end products, reflecting the higher rate of photosynthetic CO2 fixation. The proteome analysis revealed that the proteins changed in the transgenic genotypes compared to the wild-type plants were primarily associated with the regulation of the Calvin cycle and the amino acid biosynthesis. Metabolic analysis of the transgenic LA, LB and C3 plants revealed an increase in the levels of carbohydrates and also of most amino acids. Furthermore, transgenic LA and LB plants could maintain the enhanced biomass under low nitrogen conditions, where similarly-treated wild-type plants grew more slowly. The data generated in the present study confirmed that even single Chlamydomonas CCM components can be integrated into C3 plants to increase biomass, suggesting that transgenic lines combining multiple components or even a complete CCM could further increase the productivity and yield of C3 crops. RWTH Aachen University, Diss., 2017; Aachen, 1 Online-Ressource (151 Seiten) : Illustrationen, Diagramme(2017). = RWTH Aachen University, Diss., 2017 Published by Aachen

This Article examines the genesis and context of SE4All, placing the effort within both itshistorical and international policy contexts. It highlights the voluntary nature of the initiative andargues that its effective implementation and the achievement of its goals require the articulation ofan applicable international legal framework that aids the transformation of SE4All’s policy actionsinto binding international legal commitments. The article contends that such a transformation doesnot depend on the creation of entirely new legal rules or institutions. Instead, an effective frame-work for successful implementation of SE4All can be derived from existing rules of internationalhuman rights law and sustainable development law. Reliance on these twin bodies of interna-tional law will increase the prospects for SE4All to achieve energy access and related goals thatits predecessor initiatives have failed to accomplish

Devon County Council

Marine ecosystems are known to be climatea dependent, and impacts from progressing global climate change are increasingly observed and anticipated to intensify in the course of the 21st century. Under continuously high anthropogenic greenhouse gas emissions, drivers such as ocean warming, ocean acidification, and deoxygenation will increasingly affect marine ecosystems and the provision of marine ecosystem services to human societies. Environmental drivers affect organismal processes directly, but also have indirect effects through biotic interactions. Human societies are dependent on the ecosystem services provided by the oceans, and have limited adaptive capacities to changes in ecosystem service provision. An integrated evaluation of marinea human systems is thus necessary to understand coming changes, and is increasingly pursued by recent ecosystema based and integrated assessment and management approaches. The uncertainty of future climate change impacts and the interactions with the increasing anthropogenic pressures on marine systems need to be addressed. Ecological models are important tools to provide this integration of data and processes, as they can put experimental and observational data into context, and enable us to move beyond simple extrapolations of future states and experiences, creating an understanding of the changes in marine ecosystems anticipated in the future. While a wide variety of modeling approaches is available to answer specific ecological questions, a quantitative integration over different hierarchical levels, and different types of data and knowledge, is rarely achieved. The presented thesis revolves around a case study from the Barents Sea, which is among the marine regions with the earliest impacts of ocean acidification and warming expected and already observed, providing an integrative view of the impacts of these drivers on marine ecosystems and the provision of ecosystem services in the focus region. The work was built upon a thorough general analysis of available modeling approaches for modeling climate change impacts on marine fish populations (Paper 1). This analysis assessed capacities of the existing modeling approaches and recent applications, and revealed processes which need to be incorporated better in the light of recent experimental and observational results. A modeling framework to address the specific questions in the Barents Sea region was developed based on participation of stakeholders gained during personal interviews and two workshops (Paper 2). This served to incorporate their concerns and knowledge into the model structure and identify potential adaptation options for the stakeholder groups. To address one specific scientific question of high importance and uncertainty, the anticipated impacts on fish stock recruitment, an early life stage model was developed which incorporates the experimentally quantified effects of ocean acidification and warming on Atlantic cod eggs and larvae (Paper 3). This model offers a new approach to integrating empirical data on environmental and food-web drivers into recruitment projections of marine fish. Finally, an integrative fooda web model based on the structure developed in the stakeholder work and on current processa based understanding was parameterized with empirical data and estimates of organismal rates, to simulate the dynamic fluctuations in the Barents Sea food web and explore potential shifts in composition and dynamics under ocean warming and ocean acidification (Paper 4). In the thesis discussion, the papers are summarized and put into context, and the implications for the user groups in the region and possible societal adaptation options to the projected changes are highlighted. Impacts on fisheries, cultural and recreational ecosystem services, associated adaptation options for stakeholder groups, and interactions with other uses of the ocean system and expected changes under climate change are delineated. To advance ecosystema based governance in the area, the limitations in adaptation options of some user groups point to the need to better consider these groups in decisions and regulations concerning fisheries and marine areas. The Barents Sea study thus exemplifies the possibilities to integrate experiments, observations and stakeholder input into integrative assessments of marine ecosystems under climate change. Based on the insights gained from processa based modelling and stakeholder participation, it is described how understanding and projections of climate change impacts on marinea human systems can be advanced, pointing out the importance of improved interdisciplinary cooperation and communication and an integrative perspective to link across scales and subsystems a tasks to which purposefully designed models can contribute substantially.

Ressourcen stellen die Basis für eine erfolgreiche industrielle und technologische Entwicklung dar und somit auch für den Wohlstand heutiger und zukünftiger Generationen. Mit steigender Ressourcennutzung nehmen auch die (physische und sozio-ökonomische) Verfügbarkeit abiotischer und biotischer Ressourcen, die Umweltverschmutzung und die sozialen Auswirkungen durch den Abbau und Nutzung der Ressourcen zu. Um den Erfolg implementierter Strategien (und deren Maßnahmen) hinsichtlich ihres Beitrags zu einem effizienten und nachhaltigen Umgang mit Ressourcen zu bewerten, bedarf es an entsprechenden Bewertungsmethoden. Diese Dissertation stellt vier Methoden bereit um die Bewertung abiotischer und biotischer Ressourcennutzung im Kontext der Nachhaltigkeit auf Produkt- und regionaler Ebene in konsistenter Weise zu bewerten. Die Methode zur Bewertung abiotischer Ressourcen auf Produktebene betrachtet insgesamt 21 relevante Aspekte und stellt Indikatoren zur Quantifizierung bereit. Für die Bewertung der sozio-ökonomischen Einschränkungen von Lieferketten ist eine neuer Ansatz entwickelt, der geopolitische, politische und regulative Aspekte berücksichtigt. Des Weiteren sind Screening-Indikatoren verfügbar, die die gesellschaftliche Akzeptanz der Ressourcennutzung adressieren. Um die Verfügbarkeit terrestrischer biotischer Ressourcen in Produktsystemen zu bewerten, wurde eine umfassende Methode mit 25 Indikatoren erstellt. Des Weiteren wird ein Ansatz vorgestellt, der es ermöglicht eine konsistente Zusammenführung und somit auch Bewertung verschiedener Ressourcentypen zu ermöglichen. Er findet bei der Zusammenführung der entwickelten Methoden zur Bewertung abiotischer und biotischer Ressourcen Anwendung. Da die Nutzung von Ressourcen auch auf Macro-Ebene betrachtet werden muss, wurde eine Methode zur Bewertung abiotischer Ressourcen auf regionaler Ebene entwickelt, die 25 Indikatoren für die Bewertung der Kritikalität (Verfügbarkeit von Ressourcen und Vulnerabilität der Region) und der gesellschaftlichen Akzeptanz zur Verfügung stellt. Verschiedene Fallstudien wurden durchgeführt um die Anwendbarkeit der entwickelten Methoden aufzuzeigen und zu verdeutlichen, warum eine umfassende Bewertung der Ressourcennutzung notwendig ist. Die Fallstudien umfassen u.a. die Bewertung eines Smartphones, Pkw-Herstellung und Biokraftstoffe. Die Anwendbarkeit der Methoden wird zudem erhöht, indem Indikatorwerte für 36 Metalle und 4 fossile Rohstoffe zur Verfügung gestellt werden. Die Bewertung der Nutzung abiotischer und biotischer Ressourcen auf Produkt- und regionaler Ebene wird mit dieser Dissertation signifikant verbessert, indem vier wissenschaftliche Methoden zur robusten und umfassenden Bewertung aller drei Nachhaltigkeitsdimensionen bereitgestellt werden. Resources are the basis for a thriving industrial and technological development and therefore for prosperity of present and future generations. With increasing resource use, challenges with regard to (physical and socio-economic) availability of abiotic and biotic resources and raw materials, pollution of the environment as well as social impacts associated with resource extraction and use arise. To evaluate the success of strategies managing resource use more efficiently and sustainably methodologies are required to comprehensively assess resource use and related impacts. This thesis provides four methodologies to improve the assessment of abiotic and biotic resource use in the context of sustainability on product and regional level. For the method to assess abiotic resources use on product level overall 21 aspects are considered as relevant and indicator for quantification are provided. In order to determine socio-economic supply chain restrictions a new approach is developed, considering geopolitical, political and regulatory aspects affecting resource extraction and use. Further, screening indicators are established to evaluate the societal acceptance of resources with regard to compliance with social and environmental standards. To assess the availability of terrestrial biotic resources in product systems a comprehensive methodology is established, which includes 25 indicators. Further, an approach is proposed to combine assessment methodologies in a consistent way. This approach is applied to the developed method of this thesis leading to a combined methodology. The use of resources also has to be considered on macro-economic. Thus, a methodology is developed providing 25 indicators for the two dimensions criticality, consisting of the sub-dimensions (physical and socio-economic) availability and vulnerability, as well as societal acceptance. Several case studies are carried out to demonstrate the applicability of the developed methods and to confirm the need for a comprehensive assess of resource use on micro and macro level, e.g. case studies for smart phones and cars, for biofuels produced from rapeseed and soybean. The applicability of the methodologies is further enhanced by providing indicator results for 36 metals and four fossil raw materials. The assessment of abiotic and biotic resource use on product and regional level is improved significantly by establishing four scientifically robust yet applicable methodologies, which consider multiple aspects of resource use in all three sustainability dimensions.

We report a new measurement of the exclusive $e^+ e^- \to D^{(*) \pm} D^{*\mp}$ cross sections as a function of the center-of-mass energy from the $D^{(*) \pm} D^{* \mp}$ threshold through $\sqrt{s}=6.0$ GeV with initial-state radiation. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of $951$ fb$^{-1}$. The accuracy of the cross section measurement is increased by a factor of two over the first Belle study. We perform the first angular analysis of the $e^+ e^- \to D^{* \pm} D^{* \mp}$ process and decompose this exclusive cross section into three components corresponding to the $D^*$ helicities.