• Energy Research
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Whether the thermal sensitivity of an organism's traits follows the simple Boltzmann-Arrhenius model remains a contentious issue that centers around consideration of its operational temperature range and whether the sensitivity corresponds to one or a few underlying rate-limiting enzymes. Resolving this issue is crucial, because mechanistic models for temperature dependence of traits are required to predict the biological effects of climate change. Here, by combining theory with data on 1,085 thermal responses from a wide range of traits and organisms, we show that substantial variation in thermal sensitivity (activation energy) estimates can arise simply because of variation in the range of measured temperatures. Furthermore, when thermal responses deviate systematically from the Boltzmann-Arrhenius model, variation in measured temperature ranges across studies can bias estimated activation energy distributions toward higher mean, median, variance, and skewness. Remarkably, this bias alone can yield activation energies that encompass the range expected from biochemical reactions (from ~0.2 to 1.2 eV), making it difficult to establish whether a single activation energy appropriately captures thermal sensitivity. We provide guidelines and a simple equation for partially correcting for such artifacts. Our results have important implications for understanding the mechanistic basis of thermal responses of biological traits and for accurately modeling effects of variation in thermal sensitivity on responses of individuals, populations, and ecological communities to changing climatic temperatures.

Les développements des systèmes de transport, les changements dans les tendances de consommation et des conditions telles que la COVID-19 ont augmenté à la fois la demande et la charge du transport de marchandises. Étant donné que diverses entreprises transportent des marchandises dans le monde entier pour évaluer la durabilité, la vitesse et la résilience des systèmes de transport de marchandises, des systèmes de mesure de la fluidité des données et du fret sont nécessaires. Dans cette étude, un modèle de prise de décision intégré est proposé pour donner la priorité aux alternatives de mesure de la fluidité du fret. Le modèle proposé est composé de deux étapes principales. Dans la première étape, la méthodologie logarithmique des poids additifs (LMAW) basée sur les normes de Dombi est utilisée pour trouver les poids des critères. Dans la deuxième phase, une évaluation étendue basée sur la méthode de la distance de la solution moyenne (EDAS) avec Dombi onction pour l'agrégation est présentée pour déterminer les résultats finaux de classement des alternatives. Trois alternatives de mesure de la fluidité du fret sont proposées, à savoir ne rien faire, intégrer les activités de fret dans Metaverse pour mesurer la fluidité et former une gouvernance mondiale des activités de fret pour mesurer la fluidité à partir des données disponibles. Treize critères, qui sont regroupés sous quatre aspects principaux à savoir la technologie, la gouvernance, l'efficacité et la durabilité environnementale, et une étude de cas au cours de laquelle un cadre de base est formé pour que les experts évaluent les alternatives compte tenu des critères utilisés dans le processus décisionnel multicritères. Les résultats de l'étude indiquent que l'intégration des activités de fret dans Metaverse pour mesurer la fluidité est l'alternative la plus avantageuse, alors que ne rien faire est la moins avantageuse. Los desarrollos en los sistemas de transporte, los cambios en las tendencias de consumismo y condiciones como el COVID-19 han aumentado tanto la demanda como la carga en el transporte de mercancías. Dado que varias empresas transportan mercancías en todo el mundo para evaluar la sostenibilidad, la velocidad y la resistencia de los sistemas de transporte de mercancías, se necesitan sistemas de medición de datos y fluidez de la carga. En este estudio, se propone un modelo integrado de toma de decisiones para priorizar las alternativas de medición de la fluidez de la carga. El modelo propuesto se compone de dos etapas principales. En la primera etapa, se utiliza la Metodología Logarítmica de Pesos Aditivos (LMAW) basada en normas Dombi para encontrar los pesos de los criterios. En la segunda fase, se presenta una Evaluación extendida basada en el método de Distancia de la Solución Media (EDAS) con Dombi unción para la agregación para determinar los resultados finales de clasificación de las alternativas. Se proponen tres alternativas de medición de la fluidez de la carga, a saber, no hacer nada, integrar las actividades de carga en Metaverse para medir la fluidez y formar una gobernanza global de las actividades de carga para medir la fluidez a través de los datos disponibles. Trece criterios, que se agrupan en cuatro aspectos principales: tecnología, gobernanza, eficiencia y sostenibilidad ambiental, y un estudio de caso en el que se forma un marco básico para que los expertos evalúen las alternativas considerando que los criterios se utilizan en el proceso de toma de decisiones multicriterio. Los resultados del estudio indican que integrar las actividades de carga en Metaverso para medir la fluidez es la alternativa más ventajosa, mientras que no hacer nada es la menos ventajosa. Developments in transportation systems, changes in consumerism trends, and conditions such as COVID-19 have increased both the demand and the load on freight transportation. Since various companies are transporting goods all over the world to evaluate the sustainability, speed, and resiliency of freight transportation systems, data and freight fluidity measurement systems are needed. In this study, an integrated decision-making model is proposed to advantage prioritize the freight fluidity measurement alternatives. The proposed model is composed of two main stages. In the first stage, the Dombi norms based Logarithmic Methodology of Additive Weights (LMAW) is used to find the weights of criteria. In the second phase, an extended Evaluation based on the Distance from Average Solution (EDAS) method with Dombi unction for aggregation is presented to determine the final ranking results of alternatives. Three freight fluidity measurement alternatives are proposed, namely doing nothing, integrating freight activities into Metaverse for measuring fluidity, and forming global governance of freight activities for measuring fluidity through available data. Thirteen criteria, which are grouped under four main aspects namely technology, governance, efficiency, and environmental sustainability, and a case study at which a ground framework is formed for the experts to evaluate the alternatives considering the criteria are used in the multi-criteria decision-making process. The results of the study indicate that integrating freight activities into Metaverse for measuring fluidity is the most advantageous alternative, whereas doing nothing is the least advantageous one. أدت التطورات في أنظمة النقل، والتغيرات في اتجاهات النزعة الاستهلاكية، وظروف مثل COVID -19 إلى زيادة الطلب والحمل على نقل البضائع. نظرًا لأن العديد من الشركات تنقل البضائع في جميع أنحاء العالم لتقييم استدامة وسرعة ومرونة أنظمة نقل البضائع، فهناك حاجة إلى أنظمة قياس سيولة البيانات والشحن. في هذه الدراسة، يُقترح نموذج متكامل لصنع القرار للاستفادة من إعطاء الأولوية لبدائل قياس سيولة الشحن. يتكون النموذج المقترح من مرحلتين رئيسيتين. في المرحلة الأولى، يتم استخدام منهجية لوغاريتمية الأوزان المضافة (LMAW) القائمة على معايير دومبي لإيجاد أوزان المعايير. في المرحلة الثانية، يتم تقديم تقييم موسع يعتمد على طريقة المسافة من الحل المتوسط (EDAS) مع Dombi unction للتجميع لتحديد نتائج الترتيب النهائي للبدائل. يتم اقتراح ثلاثة بدائل لقياس سيولة الشحن، وهي عدم القيام بأي شيء، ودمج أنشطة الشحن في ميتافيرس لقياس السيولة، وتشكيل حوكمة عالمية لأنشطة الشحن لقياس السيولة من خلال البيانات المتاحة. ثلاثة عشر معيارًا، تم تجميعها تحت أربعة جوانب رئيسية وهي التكنولوجيا والحوكمة والكفاءة والاستدامة البيئية، ودراسة حالة يتم فيها تشكيل إطار أرضي للخبراء لتقييم البدائل مع مراعاة استخدام المعايير في عملية صنع القرار متعددة المعايير. تشير نتائج الدراسة إلى أن دمج أنشطة الشحن في ميتافيرس لقياس السيولة هو البديل الأكثر فائدة، في حين أن عدم القيام بأي شيء هو البديل الأقل فائدة.

This paper presents the application of isogeometric analysis (IGA) to the spatial discretisation of the multi-group, self-adjoint angular flux (SAAF) form of the neutron transport equation with a discrete ordinate (SN) angular discretisation. The IGA spatial discretisation is based upon non-uniform rational B-spline (NURBS) basis functions for both the test and trial functions. In addition a source iteration compatible maximum principle is used to derive the IGA spatially discretised SAAF equation. It is demonstrated that this maximum principle is mathematically equivalent to the weak form of the SAAF equation. The rate of convergence of the IGA spatial discretisation of the SAAF equation is analysed using a method of manufactured solutions (MMS) verification test case. The results of several nuclear reactor physics verification benchmark test cases are analysed. This analysis demonstrates that for higher-order basis functions, and for the same number of degrees of freedom, the FE based spatial discretisation methods are numerically less accurate than IGA methods. The difference in numerical accuracy between the IGA and FE methods is shown to be because of the higher-order continuity of NURBS basis functions within a NURBS patch as well as the preservation of both the volume and surface area throughout the solution domain within the IGA spatial discretisation. Finally, the numerical results of applying the IGA SAAF method to the OECD/NEA, seven-group, two-dimensional C5G7 quarter core nuclear reactor physics verification benchmark test case are presented. The results, from this verification benchmark test case, are shown to be in good agreement with solutions of the first-order form as well as the second-order even-parity form of the neutron transport equation for the same order of discrete ordinate (SN) angular approximation. Funding was provided by the following grants: EPSRC impact acceleration award grant reference number: EP/R511547/1, Adaptive Hierarchical Radiation Transport Methods to Meet Future Challenges in Reactor Physics (EPSRC Grant No.: EP/ J002011/1), RADIANT: A Parallel, Scalable, High Performance Radiation Transport Modelling and Simulation Framework for Reactor Physics, Nuclear Criticality Safety Assessment and Radiation Shielding Analyses (EPSRC Grant No.: EP/K503733/1)

AbstractImproving the long-term stability of perovskite solar cells is critical to the deployment of this technology. Despite the great emphasis laid on stability-related investigations, publications lack consistency in experimental procedures and parameters reported. It is therefore challenging to reproduce and compare results and thereby develop a deep understanding of degradation mechanisms. Here, we report a consensus between researchers in the field on procedures for testing perovskite solar cell stability, which are based on the International Summit on Organic Photovoltaic Stability (ISOS) protocols. We propose additional procedures to account for properties specific to PSCs such as ion redistribution under electric fields, reversible degradation and to distinguish ambient-induced degradation from other stress factors. These protocols are not intended as a replacement of the existing qualification standards, but rather they aim to unify the stability assessment and to understand failure modes. Finally, we identify key procedural information which we suggest reporting in publications to improve reproducibility and enable large data set analysis.

Nowadays, screw feeders are popular equipment in the pharmaceutical industry. However, despite the increasing research in the last decade in the manufacturing of powder-based products, there is sti...