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Recently two approaches to extend the photoluminescence imaging (PLI) technique by evaluating the dynamic properties of the sample have been presented. Time-resolved photoluminescence measurements may provide calibration-free maps of the effective minority charge carrier lifetime in silicon wafers. Due to the transient measurement they minimize errors due to lateral inhomogeneities in setup or sample, which would usually contribute linearly to steady-state PLI measurements. In this work, we will focus on mechanically shuttered time-resolved photoluminescence imaging (TR-PLI), as it provides a high measurement range down to 5 μs at low hardware costs. 26th European Photovoltaic Solar Energy Conference and Exhibition; 1463-1466

Knowledge of the carbon emissions elasticities of income and population is important both for climate change policy/negotiations and for generating projections of carbon emissions. However, previous estimations of these elasticities using the well-known STIRPAT framework have produced such wide-ranging estimates that they add little insight. This paper presents estimates of the STIRPAT model that address that shortcoming, as well as the issues of cross-sectional dependence, heterogeneity, and the nonlinear transformation of a potentially integrated variable, i.e., income. Among the findings are that the carbon emissions elasticity of income is highly robust; and that the income elasticity for OECD countries is less than one, and likely less than the non-OECD country income elasticity, which is not significantly different from one. By contrast, the carbon emissions elasticity of population is not robust; however, that elasticity is likely not statistically significantly different from one for either OECD or non-OECD countries. Lastly, the heterogeneous estimators were exploited to reject a Carbon Kuznets Curve: while the country-specific income elasticities declined over observed average income-levels, the trend line had a slight U-shape.

Protecting the environment and enjoying a high quality of life are two pursuits often viewed as being in conflict with each other, although this assumption is largely based on conventional wisdom rather than science. In the last decade the relationship between them has received increasing attention from researchers, and there has been published a number of studies investigating it. In this article, we investigate the relationship between green behaviour (GB) and subjective well-being (SWB) by reviewing the existing empirical literature on the subject. The article is divided into two reviews. In the first review we examine studies investigating the relationship between GB and SWB directly and identify variables that may explain the relationship. In the second review we examine studies that investigate relations between each of these variables and GB or SWB. Contrary to conventional wisdom, the overall finding is a positive relationship between GB and SWB, and this relationship is partially mediated by value orientation and mindfulness. Additionally, connection to nature is positively related to both GB and SWB.

We study how spillovers from water pollution cleanup in the Ganges affect social welfare in an aggregate economy consisting of Kanpur and Varanasi, two cities through which this river flows. We view pollution cleanup in both cities as a local public good and point out that if Kanpur cleans up pollution in the Ganges then Varanasi obtains some spillover benefit and vice versa. In this setting, we first solve for the Nash equilibrium amounts of pollution cleanup in the two cities when decisions about how much pollution to clean up are made simultaneously; next, we determine the equilibrium welfare levels in each city. Second, on the assumption that decisions about how much pollution to clean up are centralized, we compute the amounts of pollution cleanup that maximize aggregate welfare. Finally, we describe an inter-city transfer scheme that leads each city to choose non-cooperatively in a Nash equilibrium the same pollution cleanup amounts as those that arise when aggregate welfare is maximized.

Résumé. Les observations des changements de masse des glaciers sont essentielles pour comprendre la réponse des glaciers au changement climatique et aux impacts connexes, tels que le ruissellement régional, les changements écosystémiques et l'élévation du niveau de la mer à l'échelle mondiale. Les capteurs optiques et radar spatiaux permettent de quantifier les changements d'élévation des glaciers, et donc les changements de masse pluriannuels, à l'échelle régionale et mondiale. Cependant, les estimations d'un nombre croissant d'études montrent un large éventail de résultats avec des différences souvent au-delà des limites d'incertitude. Ici, nous présentons les résultats d'une expérience intercomparaison communautaire utilisant des données d'interférométrie stéréo optique spatiale (ASTER) et radar à ouverture synthétique (TanDEM-X) pour estimer les changements d'altitude pour des glaciers définis et des périodes cibles qui posent différents défis d'évaluation. En utilisant des modèles d'élévation numériques (DEM) fournis ou autotraités pour cinq sites de test, 12 groupes de recherche ont fourni un total de 97 ensembles de données de changement d'altitude spatiaux en utilisant diverses stratégies de traitement. La validation avec des données aéroportées a montré que l'utilisation d'une estimation d'ensemble promet de réduire les erreurs aléatoires provenant de différents instruments et méthodes de traitement, mais nécessite toujours une enquête et une correction plus complètes des erreurs systématiques. Nous avons constaté que la sélection de la scène, le traitement DEM et le co-enregistrement ont le plus grand impact sur les résultats. D'autres étapes de traitement, telles que le traitement des vides de données spatiales, les différences de périodes d'enquête ou la pénétration radar, peuvent toujours être importantes pour des cas individuels. Les recherches futures devraient se concentrer sur la mise à l'essai de différentes implémentations d'étapes de traitement individuelles (par exemple, le co-enregistrement) et aborder les questions liées aux corrections temporelles, à la pénétration radar, aux changements de zone glaciaire et à la conversion de densité. Enfin, notre communauté a clairement besoin de développer les meilleures pratiques, d'utiliser des logiciels ouverts et reproductibles et d'évaluer l'incertitude globale afin d'améliorer les comparaisons et de renforcer les connaissances sur les processus physiques dans les études de changement d'altitude des glaciers. Resumen. Observar los cambios en la masa de los glaciares es clave para comprender la respuesta de los glaciares al cambio climático y los impactos relacionados, como la escorrentía regional, los cambios en los ecosistemas y el aumento global del nivel del mar. Los sensores ópticos y de radar transportados por el espacio permiten cuantificar los cambios de elevación de los glaciares y, por lo tanto, los cambios de masa plurianuales, a escala regional y global. Sin embargo, las estimaciones de un número creciente de estudios muestran una amplia gama de resultados con diferencias que a menudo van más allá de los límites de incertidumbre. Aquí, presentamos el resultado de un experimento de intercomparación basado en la comunidad que utiliza datos estéreo óptico a bordo del espacio (ASTER) e interferometría de radar de apertura sintética (TanDEM-X) para estimar los cambios de elevación para glaciares definidos y períodos objetivo que plantean diferentes desafíos de evaluación. Utilizando modelos digitales de elevación (DEM) proporcionados o autoprocesados para cinco sitios de prueba, 12 grupos de investigación proporcionaron un total de 97 conjuntos de datos de cambio de elevación a bordo del espacio utilizando varias estrategias de procesamiento. La validación con datos aéreos mostró que el uso de una estimación de conjunto es prometedor para reducir los errores aleatorios de diferentes instrumentos y métodos de procesamiento, pero aún requiere una investigación y corrección más exhaustivas de los errores sistemáticos. Descubrimos que la selección de escenas, el procesamiento de DEM y el corregistro tienen el mayor impacto en los resultados. Otros pasos de procesamiento, como el tratamiento de vacíos de datos espaciales, las diferencias en los períodos de encuesta o la penetración del radar, aún pueden ser importantes para casos individuales. La investigación futura debe centrarse en probar diferentes implementaciones de pasos de procesamiento individuales (por ejemplo, registro conjunto) y abordar cuestiones relacionadas con correcciones temporales, penetración de radar, cambios en el área de los glaciares y conversión de densidad. Finalmente, existe una clara necesidad de que nuestra comunidad desarrolle las mejores prácticas, use software abierto y reproducible y evalúe la incertidumbre general para mejorar la intercomparación y potenciar los conocimientos de los procesos físicos en los estudios de cambio de elevación de glaciares. Abstract. Observations of glacier mass changes are key to understanding the response of glaciers to climate change and related impacts, such as regional runoff, ecosystem changes, and global sea-level rise. Spaceborne optical and radar sensors make it possible to quantify glacier elevation changes, and thus multi-annual mass changes, on a regional and global scale. However, estimates from a growing number of studies show a wide range of results with differences often beyond uncertainty bounds. Here, we present the outcome of a community-based inter-comparison experiment using spaceborne optical stereo (ASTER) and synthetic aperture radar interferometry (TanDEM-X) data to estimate elevation changes for defined glaciers and target periods that pose different assessment challenges. Using provided or self-processed digital elevation models (DEMs) for five test sites, 12 research groups provided a total of 97 spaceborne elevation-change datasets using various processing strategies. Validation with airborne data showed that using an ensemble estimate is promising to reduce random errors from different instruments and processing methods, but still requires a more comprehensive investigation and correction of systematic errors. We found that scene selection, DEM processing, and co-registration have the biggest impact on the results. Other processing steps, such as treating spatial data voids, differences in survey periods, or radar penetration, can still be important for individual cases. Future research should focus on testing different implementations of individual processing steps (e.g. co-registration) and addressing issues related to temporal corrections, radar penetration, glacier area changes, and density conversion. Finally, there is a clear need for our community to develop best practices, use open, reproducible software, and assess overall uncertainty in order to enhance inter-comparison and empower physical process insights across glacier elevation-change studies. الخلاصة. تعتبر ملاحظات التغيرات في كتلة الأنهار الجليدية أساسية لفهم استجابة الأنهار الجليدية لتغير المناخ والآثار ذات الصلة، مثل الجريان السطحي الإقليمي وتغيرات النظام الإيكولوجي وارتفاع مستوى سطح البحر العالمي. تتيح أجهزة الاستشعار البصرية والرادارية المحمولة في الفضاء قياس التغيرات في ارتفاع الأنهار الجليدية، وبالتالي التغيرات الكتلية متعددة السنوات، على نطاق إقليمي وعالمي. ومع ذلك، تظهر التقديرات من عدد متزايد من الدراسات مجموعة واسعة من النتائج مع وجود اختلافات غالبًا ما تتجاوز حدود عدم اليقين. هنا، نقدم نتائج تجربة مقارنة مجتمعية باستخدام بيانات الاستريو البصري المحمول في الفضاء (ASTER) وبيانات قياس التداخل بالرادار ذي الفتحة الاصطناعية (TanDEM - X) لتقدير تغيرات الارتفاع للأنهار الجليدية المحددة والفترات المستهدفة التي تشكل تحديات تقييم مختلفة. باستخدام نماذج الارتفاع الرقمية المقدمة أو ذاتية المعالجة (DEMs) لخمسة مواقع اختبار، قدمت 12 مجموعة بحثية ما مجموعه 97 مجموعة بيانات لتغيير الارتفاع المحمول في الفضاء باستخدام استراتيجيات معالجة مختلفة. أظهر التحقق من البيانات المحمولة جواً أن استخدام تقدير المجموعة يعد بتقليل الأخطاء العشوائية من الأدوات وطرق المعالجة المختلفة، ولكنه لا يزال يتطلب تحقيقًا أكثر شمولاً وتصحيحًا للأخطاء المنهجية. وجدنا أن اختيار المشهد ومعالجة DEM والتسجيل المشترك لها أكبر تأثير على النتائج. يمكن أن تظل خطوات المعالجة الأخرى، مثل معالجة فراغات البيانات المكانية أو الاختلافات في فترات المسح أو اختراق الرادار، مهمة للحالات الفردية. يجب أن تركز الأبحاث المستقبلية على اختبار التطبيقات المختلفة لخطوات المعالجة الفردية (مثل التسجيل المشترك) ومعالجة القضايا المتعلقة بالتصحيحات الزمنية واختراق الرادار وتغيرات المنطقة الجليدية وتحويل الكثافة. أخيرًا، هناك حاجة واضحة لمجتمعنا لتطوير أفضل الممارسات، واستخدام برامج مفتوحة وقابلة للتكرار، وتقييم عدم اليقين العام من أجل تعزيز المقارنة البينية وتمكين رؤى العمليات المادية عبر دراسات تغيير ارتفاع الأنهار الجليدية.

The project steering committee has taken a phased approach to the development of a Circumpolar Local Environmental Observer Network. Phase One activities are on track to be completed and delivered to the Arctic Council Ministers at the May 2017 Ministerial in Fairbanks, Alaska. ; Community-based monitoring networks in rural communities can help connect those with indigenous, traditional, local and ecological knowledge with scientists, policymakers and technical experts to develop trust, collaborative approaches, and solutions to human health and environmental problems resulting from contaminants and pollution. Strengthening this cooperation and increasing collaboration will bring benefits to commmunities across the Arctic.

A highly efficient nonlinear frequency-domain solution method is proposed and employed to investigate the aerodynamic and aeromechanical performances of an oscillating wind turbine blade aerofoil in this study. Extensive validations of a frequency-domain method against an experiment as well as a typical time-domain solution method are provided in this paper. An experiment is also designed and conducted to measure pressure distributions over an aerofoil as well as to validate the numerical model. Unsteady pressure distributions and aeroelasticity parameters of the oscillating NACA0012 aerofoil are computed at various angles of attack and Reynolds numbers. Results indicate that the difference of unsteady pressure distributions between the two surfaces of the aerofoil becomes larger as the angle of attack is increased, whereas the flow separation on the suction surface is reduced by raising the Reynolds number. The turbulent flow develops in the downstream region due to the laminar vortex shedding at lower Reynolds numbers. It is also revealed that the Reynolds number has an impact on the aeroelasticity, and the aerodynamic damping value is larger at higher Reynolds numbers. The comparison between the frequency-domain method and the time-domain method shows that the frequency-domain method is not only accurate but also computationally very efficient as the computation time is reduced by 90%.

Changing PV market conditions foster the use of PV storage systems and bring new challenges to the grid. This paper analyzes the influence of PV and PV battery systems on the voltage unbalance and the voltage magnitude. Different system topologies are evaluated by simulating their behavior in two different test grids. A sensitivity analysis is performed varying the size of the PV system, the size of the battery, the grid penetration of the systems and the phase connection. The analysis shows that voltage unbalance problems can occur in case of same phase connection of the systems. The results suggest that PV battery systems mitigate the problem for the two example grids depending on the PV power and battery size. For grids with equally distributed phase connections of either PV or PV battery systems, no violations of the voltage unbalance criterion are observed. 27th European Photovoltaic Solar Energy Conference and Exhibition; 3822-3828