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The demand for effective cooling and energy storage technologies is growing continuously. The climatic changes, miniaturization, and digitalization have redefined the technological development in the cooling and energy storage industries. The global focus is on the environmental-friendly, efficient, sustainable, and scalable cooling technologies. Owing to all these factors, green alternatives to the traditional air-conditioning and refrigeration are gaining momentum. One of such green alternatives is the electrocaloric effect (ECE). The electrocaloric effect is observed in dielectric materials as they undergo an adiabatic temperature change or an isothermal entropy change under an externally applied/removed electric field. Dielectric materials are capable to store the electrical energy as well. Therefore, they are particularly interesting for the new cooling and energy storage technologies. In this work, a ferroelectric relaxor polymer, namely, Poly(vinylidene fluoride – trifluoroethylene – chlorofluoroethylene) (P(VDF–TrFE–CFE) is investigated for the electrocaloric effect through the direct and the indirect methods. The electrical energy storage properties of different compositions of P(VDF–TrFE–CFE) and their nanocomposites with inorganic 0D nanofillers are studied. Initially, the relaxor properties in six different compositions of P(VDF–TrFE–CFE) are studied. Out of these six compositions, the three compositions, 51.3/48.7/6.2, 59.8/40.2/7.3, and 70/30/8.1, are analyzed for the first time. The field induced phase transition results in a double hysteresis loop in a few compositions. Through the direct electrocaloric measurements, it is observed that the electric field induced phase transition results in a higher electrocaloric temperature change. The indirect electrocaloric measurements are conducted with and without compensating the leakage current. It is shown that the indirect method can lead to erroneous results due to the leakage current. The results obtained through the indirect measurements conducted with the leakage current compensation are comparable to the direct measurements. The electrical energy storage properties of the neat terpolymers and their nanocomposites are compared. It is observed that the stored and discharged energy densities of the nanocomposites are superior to the neat terpolymers. Dissertation, Universität Duisburg-Essen, 2022

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.

With the increase in energy of the Large Hadron Collider to a centre-of-mass energy of 13 TeV for Run 2, events with dense environments, such as in the cores of high-energy jets, became a focus for new physics searches as well as measurements of the Standard Model. These environments are characterized by charged-particle separations of the order of the tracking detectors sensor granularity. Basic track quantities are compared between 3.2 fb$^{-1}$ of data collected by the ATLAS experiment and simulation of proton-proton collisions producing high-transverse-momentum jets at a centre-of-mass energy of 13 TeV. The impact of charged-particle separations and multiplicities on the track reconstruction performance is discussed. The efficiency in the cores of jets with transverse momenta between 200 GeV and 1600 GeV is quantified using a novel, data-driven, method. The method uses the energy loss, dE/dx, to identify pixel clusters originating from two charged particles. Of the charged particles creating these clusters, the measured fraction that fail to be reconstructed is $0.061 \pm 0.006 \textrm{(stat.)} \pm 0.014 \textrm{(syst.)}$ and $0.093 \pm 0.017 \textrm{(stat.)}\pm 0.021 \textrm{(syst.)}$ for jet transverse momenta of 200-400 GeV and 1400-1600 GeV, respectively. The European physical journal / C 77(10), 673 (2017). doi:10.1140/epjc/s10052-017-5225-7 Published by Springer, Berlin

In this doctoral thesis, I develop a Kantian political theory for anthropogenic climate change. I argue that human-induced climatic changes are a form of collective domination. My analysis adds an outspokenly democratic perspective to the public debate on climate change, which is increasingly marked by a new distrust in democracy. I first emphasise the need for a political theory of climate change. Climate change raises many important normative questions: How serious a problem is climate change and why? What is a just and equitable answer to climate change? Who is responsible for tackling climate change? Many answers, often opposing, have been offered. Opposition often results from deeply engrained disagreements over appropriate ethical standards. To avoid imposing our own views on these important questions, however well-conceived we think they are, an approach is needed that guides our normative theorising under the condition of this de facto disagreement over ethical standards. While normative political theory is specifically tailored to operate under this condition, I contend that a Kantian political theory provides an especially compelling way to do so. At the heart of Kantian political theory is the notion of domination. However, the process of adapting the Kantian notion of domination to climate change faces an important challenge. We are accustomed to thinking of domination in terms of the paradigm example of a master–slave relationship. The relationship that climate change establishes among various agents differs, however, from this paradigm example in two significant ways. First, the relevant agents will almost certainly never meet each other (indirect relationship), and, second, individual agents cannot bring about the dominating climatic changes on their own (collective relationship). Therefore, I advance an additional understanding of the notion of force that is geared towards the indirect nature of climate change. Drawing on the philosophical debate about coercion and the literature on forced migration, I argue that it is through changes to the option-set of a rational agent that climatic changes and, thus, the agents who cause them, exert force. This rendering of force sheds a clear light on the conceptual basis for speaking of forced climate displacement and provides a striking instance of domination as Kantians understand it. Finally, I develop an understanding of the collective nature of climate change. I argue that the normativity of individual emissions of greenhouse gases, such as through a sunny Sunday afternoon joyride, is different from other trivial cases of wrongdoing, such as delivering a kick to the shins. While the debate on this question has been focused almost exclusively on quantitative aspects of the respective causal chains that link the individual actions to the harm they cause, I contend that their difference lies in a neglected qualitative feature: Contrary to the harm done in more trivial cases, climate harm is a non-aggregative outcome. It is, therefore, a wrong that is committed not by you or me, but by us collectively. It is the political wrong of domination that Kantian political theory seeks to identify. History provides us with many examples of only poorly disguised faces of domination. I argue that our unprecedented ability to change the climate is yet another face of domination, even though it may be less apparently so. It is here that the proposed analysis emphatically reasserts a democratic perspective on climate change. Climate domination can be overcome only if we ensure that the opposing views of every person are taken into account when answering the important normative questions climate change raises. Thus, a Kantian political theory account of climate change urges us to place the question of transnational and intergenerational democracy at the top of our agenda. The resulting political theory of climate change can be read as adding a new facet to a critique that was introduced as early as 1991 by Anil Agarwal and Sunita Narain and was directed at what they defiantly labelled as ‘environmental colonialism’. Dissertation, Universität Duisburg-Essen, 2020

The role of sustainability practices around the world in supply chain made it a very critical point to measure not only the entities’ performance but also the sustainability practices in supply chain overall. This study takes Logistics Service Providers (LSPs) as the field of study in Egypt. The main aim of this study is to propose a new Sustainable Logistics Service Quality (SLSQ) framework through reviewing Sustainable Service Quality (SSQ), Egyptian laws related to Sustainability and Logistics Service Quality (LSQ) for enhancing Customer Satisfaction (CS) and Relationship Quality (RQ) in Egypt. This research starts with the literature review to derive out the research questions. Four research questions were presented in order to state the research gap. This research integrates the concept of SSQ and LSQ as one process to be evaluated from the customer perspective as called SLSQ. After that, it measures the effect of SLSQ on LSP’s customer satisfaction and relationship quality. To collect the research data, a mixed method approach has been used in this research, starting from the semi-structured interviews in phase one (part one) to validate the SSQ elements. In phase one (part two), the SLSQ elements have been generated and validated through evaluation tools. Finally, in phase two, the questionnaire is designed and distributed to the target sample. The results show that SLSQ would have a significant positive effect on customer satisfaction. The findings show that customers satisfied with SLSQ will partially support the relationship between an LSP and its customers. Moreover, the findings show that CS fully mediates the relation between SLSQ and RQ. SLSQ elements focused mainly on sustainable transport, time, product condition, training programmes and collaboration. These aspects are the ones that Egyptian LSPs should consider when they present services, and the Egyptian government should consider these aspects as a power to make a sustainable development in LSP field. Dissertation, Universität Duisburg-Essen, 2021