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Improving efficiency, reducing expenses, and ensuring sustainability in today’s competitive market is made possible by optimising the performance of the food supply chain (FSC). A strong decision-making framework is required to overcome obstacles including high transportation and production costs, uneven quality, and the impact on the environment. To solve these problems, this paper presents an all-inclusive multi-criteria decision making (MCDM) framework that uses enhanced relative utility and nonlinear standardisation (ERUNS) to rank alternatives, Logarithmic percentage change-driven objective weighing (LOPCOW) to determine objective weights, and subjective weight assignment by ratio analysis (SWARA) to determine subjective criterion weights. LOPCOW offers objective weights grounded in facts and indifference thresholds, whereas SWARA records decision-makers (DMs) preferences in weighing factors like sustainability and cost efficiency. The ERUNS methodology then uses utility degree assessments and matrix standardization to rank and evaluate alternatives. An improved method of assessment is to make use of intuitionistic fuzzy sets (IFS), which deal with ambiguity by adding membership, non-membership, and hesitation levels. By merging subjective and objective data, this integrated method maximizes FSC performance, provides useful insights for enhancing overall efficiency and sustainability, and offers a viable answer to contemporary difficulties. It also offers helpful insights for improving overall efficiency and sustainability, and it provides a practical response to the challenges that are now being faced.

Advanced airborne equipment liquid cooling system presents the development trend of multiple pumps in parallel, centralised heat dissipation and high efficiency circulation, but this type of system has the characteristics of many variable parameters and strong non-linearity, which makes the system operation and control become extraordinarily complex, posing a serious challenge to the system performance. Although some progress has been made in the current optimization of liquid cooling system performance, there are still gaps such as insufficient consideration of the multi-objective optimization problem and limited optimization effect. To fill this research gap, this study takes minimum specific energy consumption, minimum flow deviation and minimum impeller load as the optimization objectives, establishment of multi-objective optimization model for liquid-cooled power unit, the optimal solution set of the Pareto model is solved using the multi-objective grey wolf optimization algorithm (MOGWO), and the optimal solution set is substituted for the optimal solution, and the evaluation indexes are designed in combination with the actual working conditions to obtain the optimal schedule. By example analysis, the optimized system under variable operating conditions, the impeller load and specific energy consumption decreased by 16.88% and 3.64% respectively, while the rise in flow deviation was controlled within 0.76%. The newly established optimisation model effectively mitigates potential safety hazards during system operation. Finally, by combining all the indicators, three scheduling options are provided under variable operating conditions, focusing on reliability and economy, overall balance and high-precision flow, respectively, in order to adapt to the diversified requirements of different operating environments.

The performance capabilities of an axially laminated anisotropic rotor (ALA) in a high-speed synchronous reluctance motor (SynRM) were studied. A 12 kW ALASynRM was designed as an alternative to a high-speed induction motor (IM) with a solid rotor. The electromagnetic design was implemented taking into account possible issues related to the new manufacturing methods, which require thicker rotor layers than in a typical ALA. The ALASynRM shows a higher efficiency than the corresponding IM with a smooth or slitted solid rotor equipped with copper end rings. To verify the design method, a prototype IM with a smooth solid rotor was built and tested. In the analysis, it was found that, similar to IMs, in an ALASynRM a considerable part of losses takes place in the rotor despite the absence of slip-related losses in the SynRM. The distribution of eddy current losses in the ALA rotor is significantly uneven. The torque ripple in the ALASynRM is considerably larger than the corresponding ripple in IMs.

To identify the DC bias state of transformers, a DC bias state identification method of transformer based on wavelet singular entropy is proposed in this paper. The vibration principle of transformers under DC bias has been analyzed. By combining continuous wavelet transform, singular value decomposition, and information entropy, the analysis method of wavelet singular entropy is proposed. The vibration signal of the transformer before and after DC bias is transformed by continuous wavelet transform, and then the wavelet time-frequency diagram is compared and analyzed. Furthermore, the DC bias state of the transformer is identified by wavelet singular entropy of vibration signal. The wavelet singular entropy under different states is in different numerical ranges, and the wavelet singular entropy of vibration signal under DC bias is significantly greater than that under no DC bias. The wavelet singular entropy effectively reflects the DC bias state of transformers. Then the proposed method is applied to a 500 kV transformer and a 220 kV transformer in the China Southern Power Grid. The results show that the proposed method can accurately and effectively identify the DC bias state of transformers.

Ce travail aborde le problème d'une conception de tuyère abordée à travers une stratégie d'optimisation multi-objectifs où les équations gouvernantes de la dynamique des fluides modélisent les phénomènes. Le débit de liquide et la longueur de la buse sont considérés comme les critères de conception. Deux variantes d'évolution différentielle sont proposées pour obtenir un ensemble de configurations de conception qui présente des synergies nombreuses et différentes entre les critères de conception. La première variante est basée sur la métrique de performance Hypervolume (MODE-HVR) et la seconde inclut le concept de e-dominance (MODE-HVeR). Une étude comparative est réalisée avec d'autres optimiseurs issus d'approches de recherche bien établies pour l'optimisation multi-objectifs tels que les algorithmes basés sur la dominance de Pareto (NSGA-II et SPEA2), la décomposition (MOEA/D), la métrique (SMS-EMOA) et l'hybride (NSGA-III). Sur la base des indicateurs d'espacement et d'hypervolume des fronts de Pareto obtenus, les algorithmes d'optimisation proposés peuvent fournir plus de solutions de conception, favorisant la reconfigurabilité (synergie) dans la conception de la buse. Par conséquent, la stratégie de conception multi-objectifs permet au concepteur d'avoir une large gamme de solutions et de choisir la plus appropriée pour une application particulière, par rapport à une conception traditionnelle où les deux critères de conception sont considérés comme une seule fonction agrégée. Este trabajo aborda el problema de un diseño de toberas abordado a través de una estrategia de optimización multiobjetivo donde las ecuaciones gobernantes de la dinámica de fluidos modelan los fenómenos. El caudal de líquido y la longitud de la boquilla se consideran como los criterios de diseño. Se proponen dos variantes de Evolución Diferencial para obtener un conjunto de configuraciones de diseño que presenta numerosas y diferentes sinergias entre los criterios de diseño. La primera variante se basa en la métrica de rendimiento de hipervolumen (MODE-HVR) y la segunda incluye el concepto de e-dominancia (MODE-HVeR). Se realiza un estudio comparativo con otros optimizadores de enfoques de búsqueda bien establecidos para la optimización multiobjetivo como algoritmos basados en dominancia de Pareto (NSGA-II y SPEA2), descomposición (MOEA/D), métrica (SMS-EMOA) e híbrido (NSGA-III). Con base en los indicadores de Espaciamiento e Hipervolumen de los frentes de Pareto obtenidos, los algoritmos de optimización propuestos pueden proporcionar más soluciones de diseño, promoviendo la reconfigurabilidad (sinergia) en el diseño de la boquilla. Por lo tanto, la estrategia de diseño multiobjetivo permite al diseñador tener una amplia gama de soluciones y elegir la más adecuada para una aplicación en particular, en comparación con un diseño tradicional donde ambos criterios de diseño se consideran como una sola función agregada. This work deals with the problem of a nozzle design addressed through a multi-objective optimization strategy where governing equations of fluid dynamics model the phenomena. The liquid flow rate and the nozzle length are considered as the design criteria. Two Differential Evolution variants are proposed to obtain a set of design configurations that presents numerous and different synergies between the design criteria. The first variant is based on the Hypervolume performance metric (MODE-HVR) and the second one includes the e-dominance concept (MODE-HVeR). A comparative study is performed with other optimizers from well-established search approaches for multi-objective optimization such as algorithms based on Pareto dominance (NSGA-II and SPEA2), decomposition (MOEA/D), metric (SMS-EMOA) and hybrid (NSGA-III). Based on the Spacing and Hypervolume indicators of the obtained Pareto fronts, the proposed optimization algorithms can provide more design solutions, promoting the reconfigurability (synergy) in the nozzle design. Hence, the multi-objective design strategy allows the designer to have a wide range of solutions and to choose the most suitable one for a particular application, compared with a traditional design where both design criteria are considered as a single aggregate function. يتناول هذا العمل مشكلة تصميم الفوهة التي يتم تناولها من خلال استراتيجية تحسين متعددة الأهداف حيث تقوم معادلات ديناميكيات الموائع الحاكمة بنمذجة الظواهر. يعتبر معدل تدفق السائل وطول الفوهة من معايير التصميم. يُقترح نوعان من التطور التفاضلي للحصول على مجموعة من تكوينات التصميم التي تقدم العديد من أوجه التآزر المختلفة بين معايير التصميم. يعتمد المتغير الأول على مقياس أداء الحجم الزائد (MODE - HVR) ويتضمن الثاني مفهوم الهيمنة الإلكترونية (MODE - HVeR). يتم إجراء دراسة مقارنة مع محسنات أخرى من مناهج البحث الراسخة للتحسين متعدد الأهداف مثل الخوارزميات القائمة على هيمنة باريتو (NSGA - II و SPEA2)، والتحلل (MOEA/D)، والمتري (SMS - EMOA) والهجين (NSGA - III). استنادًا إلى مؤشرات التباعد والحجم المفرط لواجهات باريتو التي تم الحصول عليها، يمكن أن توفر خوارزميات التحسين المقترحة المزيد من حلول التصميم، مما يعزز قابلية إعادة التكوين (التآزر) في تصميم الفوهة. وبالتالي، فإن استراتيجية التصميم متعدد الأهداف تسمح للمصمم بالحصول على مجموعة واسعة من الحلول واختيار أنسبها لتطبيق معين، مقارنة بالتصميم التقليدي حيث يعتبر كلا معياري التصميم بمثابة وظيفة مجمعة واحدة.

H-polarization, along with E-polarization, indicates the lateral variations of the Earth conductivity, which influence the induced electric field distribution. The coast effect is a typical H-polarization phenomenon that causes local geoelectric field enhancement in coastal areas and significantly affects the geomagnetically induced currents (GIC) distributions in power grids. The influences of H-polarization on geoelectric fields and GIC form the basis for further research on power grid disasters resulting from magnetic storms. In this paper, block and thin-shell models of the coast effect are established, and the electric field distribution in the case of H-polarization is calculated using the finite element method. The results demonstrate the effects of the conductivity, frequency, and distance from the interface of a different conductivity on electric field distortion. Additionally, the relationship between H-polarization and GIC in power grids is investigated, demonstrating that the GIC can be influenced within 100 km in the H-polarization case. The methods and results provide a theoretical basis for GIC risk assessment and development of a control strategy for the power grid.

En los países del sur de Asia, incluidos Bangladesh, India y Pakistán, el escenario energético actual se considera no sostenible debido a diversas cuestiones, como las opciones económicas, ambientales, geopolíticas y tecnológicas para la explotación de la energía y el volumen insignificante del comercio regional de energía. Sin embargo, dentro de la región, India está liderando una fase de transición energética y transformación económica a través del desarrollo de energías renovables. Los países deben mostrar buenos resultados en el desarrollo de sus fuentes renovables siguiendo el rápido ritmo de las energías renovables en todo el mundo. Este artículo ofrece una visión general del escenario energético, el crecimiento de las energías renovables, la evolución y el enfoque de la política energética al resaltar los desafíos y barreras clave para la combinación energética ecológica de los países. Es importante destacar que el documento evalúa la combinación energética actual en el sur de Asia, destacando la anomalía de sus perspectivas futuras basadas en combustibles fósiles, sus ambiciones de avanzar hacia una menor contaminación ambiental y una combinación energética sostenible a través de un análisis FODA de herramientas estratégicas; fortalezas, debilidades, oportunidades y amenazas (FODA). En particular, este estudio examina las políticas gubernamentales para expandir la implementación de fuentes renovables con una visión de la estructura regulatoria existente del sector energético. Los hallazgos de la investigación presentada sugieren que para lograr el ambicioso objetivo de reducir la descarga de emisiones hasta en un 30% para el año 2030 en el marco de las Contribuciones Previstas Determinadas a Nivel Nacional (INDC), los gobiernos de los tres países deben tomar medidas preventivas. Incluye la reducción gradual de los subsidios a los combustibles fósiles, la integración del mercado dentro de la región y la rápida realización de las iniciativas existentes a través de una fuerte voluntad política, una buena gobernanza, la adopción de las últimas tecnologías y un plan de acción pragmático, y la cooperación energética en toda la región. Dans les pays d'Asie du Sud, y compris le Bangladesh, l'Inde et le Pakistan, le scénario énergétique actuel est considéré comme non durable en raison de divers problèmes tels que les options économiques, environnementales, géopolitiques et technologiques pour l'exploitation de l'énergie et le volume négligeable du commerce régional de l'énergie. Bien que, dans la région, l'Inde mène une phase de transition énergétique et de transformation économique grâce au développement des énergies renouvelables. Les pays doivent bien montrer dans le développement de leurs sources renouvelables à la suite du rythme rapide des énergies renouvelables dans le monde entier. Cet article offre un aperçu du scénario énergétique, de la croissance des énergies renouvelables, de l'évolution et de l'approche de la politique énergétique en soulignant les principaux défis et obstacles pour le mix énergétique écologique des pays. Il est important de noter que le document évalue le bouquet énergétique actuel en Asie du Sud, en soulignant l'anomalie de ses perspectives d'avenir basées sur les combustibles fossiles, ses ambitions de réduire la pollution environnementale et son bouquet énergétique durable grâce à une analyse SWOT d'outil stratégique ; forces, faiblesses, opportunités et menaces (SWOT). En particulier, cette étude examine les politiques gouvernementales visant à étendre la mise en œuvre des sources renouvelables avec un aperçu de la structure réglementaire existante du secteur de l'énergie. Les résultats de recherche présentés suggèrent que pour atteindre l'objectif ambitieux de réduire les rejets d'émissions jusqu'à 30 % d'ici 2030 dans le cadre des contributions prévues déterminées au niveau national (CPDN), les gouvernements des trois pays doivent prendre des mesures préventives. Il comprend la réduction progressive des subventions sur les combustibles fossiles, l'intégration du marché dans la région et la réalisation rapide des initiatives existantes grâce à une forte volonté politique, à une bonne gouvernance, à l'adoption des dernières technologies, à un plan d'action pragmatique et à une coopération énergétique dans toute la région. In the South Asian countries, including Bangladesh, India, and Pakistan, the current energy scenario is considered non-sustainable due to diverse issues such as economic, environmental, geopolitical, technological options for energy exploitation, and negligible volume of regional energy trade. Though, within the region, India is leading a phase of energy transition and economic transformation through renewable energy development. The countries need to exhibit well in the development of their renewable sources following the rapid pace of renewable energies worldwide. This article offers an overview of the energy scenario, growth of renewable energies, evolution, and approach for energy policy by highlighting key challenges and barriers for the ecological energy mix of the countries. Importantly, the paper assesses the current energy mix in South Asia, highlighting the anomaly of its fossil fuel-based future outlook, its ambitions to move towards less environmental pollution, and sustainable energy mix through a strategic tool SWOT analysis; strengths, weaknesses, opportunities, and threats (SWOT). In particular, this study examines the government policies to expand the implementation of renewable sources with an insight into the existing regulatory structure of the energy sector. The presented research findings suggest that to achieve the ambitious target to reduce emission discharge by up to 30% by the year 2030 under Intended Nationally Determined Contributions (INDCs), the Governments of the three countries must take preemptive measures. It includes the stage-wise reduction of subsidies on fossil fuels, market integration within the region, and swift realization of the existing initiatives through strong political will, good governance, adoption of the latest technologies, and a pragmatic action plan, and energy cooperation across the region. في بلدان جنوب آسيا، بما في ذلك بنغلاديش والهند وباكستان، يعتبر سيناريو الطاقة الحالي غير مستدام بسبب قضايا متنوعة مثل الخيارات الاقتصادية والبيئية والجيوسياسية والتكنولوجية لاستغلال الطاقة، وحجم ضئيل من تجارة الطاقة الإقليمية. على الرغم من أن الهند، داخل المنطقة، تقود مرحلة انتقال الطاقة والتحول الاقتصادي من خلال تطوير الطاقة المتجددة. تحتاج البلدان إلى أن تظهر أداءً جيدًا في تطوير مصادرها المتجددة بعد الوتيرة السريعة للطاقات المتجددة في جميع أنحاء العالم. تقدم هذه المقالة لمحة عامة عن سيناريو الطاقة، ونمو الطاقات المتجددة، والتطور، ونهج سياسة الطاقة من خلال تسليط الضوء على التحديات والحواجز الرئيسية لمزيج الطاقة البيئية للبلدان. والأهم من ذلك، تقوم الورقة بتقييم مزيج الطاقة الحالي في جنوب آسيا، مع تسليط الضوء على الشذوذ في توقعاتها المستقبلية القائمة على الوقود الأحفوري، وطموحاتها للتحرك نحو تلوث بيئي أقل، ومزيج الطاقة المستدامة من خلال تحليل SWOT الاستراتيجي للأداة ؛ نقاط القوة والضعف والفرص والتهديدات (SWOT). على وجه الخصوص، تبحث هذه الدراسة في السياسات الحكومية لتوسيع تنفيذ مصادر الطاقة المتجددة مع نظرة ثاقبة على الهيكل التنظيمي الحالي لقطاع الطاقة. تشير نتائج البحث المقدمة إلى أنه لتحقيق الهدف الطموح المتمثل في الحد من تصريف الانبعاثات بنسبة تصل إلى 30 ٪ بحلول عام 2030 بموجب المساهمات المقررة المحددة وطنيًا (INDCs)، يجب على حكومات البلدان الثلاثة اتخاذ تدابير وقائية. ويشمل ذلك التخفيض التدريجي للإعانات على الوقود الأحفوري، وتكامل الأسواق داخل المنطقة، والإدراك السريع للمبادرات القائمة من خلال الإرادة السياسية القوية، والحكم الرشيد، واعتماد أحدث التقنيات، وخطة عمل عملية، والتعاون في مجال الطاقة في جميع أنحاء المنطقة.

The present paper considers the evaluation of temperature regulated and unregulated charging strategies to select the appropriate one to ensure extended battery life with reduced charging time. Temperature regulated pulse charging (TRPC) and temperature regulated reflex charging (TRRC) are compared with the Constant current-constant voltage (CC-CV) charging strategy. In the case of CC-CV charging temperature of the battery rises with the magnitude of the current being injected and cannot be regulated without any external cooling arrangement. Impact on the State of health (SOH) and the expected lifespan of the battery are considered as the parameters of evaluation. Temperature regulated strategies are implemented through a discrete electro-thermal model, which acts as a temperature estimator. The co-efficient of the estimators corresponds to the battery parameters such as internal resistance and thermal time constants, entropy, etc. Temperature regulation is ensured in the three identified sections of charge deposited vs magnitude of the injected current. Three sections are identified as sections where the injected current is not sufficient to raise the battery temperature to set limit or not and the level of charge submitted as compared to normal charging. Experimentation is carried with 12 V, 26 Ah Valve regulated lead-acid battery to justify that increase in temperature reference of regulation allows submission of higher charge for the same charging rate. It is demonstrated that TRPC results in a significant reduction (≈60%) in charging time as compared to CC-CV and TRRC. For the same charging time as achieved with TRPC, TRPC results in almost double the expected life of operation and better SOH as compared to CC-CV and TRRC.