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Abstract Global warming is a major challenge that we are facing today that involves the emission of harmful greenhouse gases like carbon dioxide (CO 2 ) into the atmosphere. Pressurized pipelines are considered to be the most efficient and reliable way to transport CO 2 due to the high density and low viscosity of CO 2 . Any accidental discharge from such high pressure pipelines may result in significant damage to the ambient atmosphere and a powerful threat to human health. The unusual phase transition behavior of CO 2 post leak can pose challenging risks for modeling the safe transportation of CO 2 , which is one of the most critical process design considerations in a carbon capture and storage (CCS) area. The current consequence model described in this work predicts the transient jet release rates and the concentration variations of pure CO 2 over a given period of time and distance in Fluent 16.2. This has been validated against experimental work carried out by BP’s DF1 project at the Spadeadam site. The work has been extended to study the effect of terrain on the final downwind concentration of CO 2 . This consequence model could successfully predict the minimum safe distances to populated areas and can be used as a risk assessment tool for planning emergency response in case of pipeline leakage during CO 2 transport.

Los nodos de red de sensores inalámbricos tienen una energía limitada, la forma de emplear la energía limitada de manera eficiente para realizar una transmisión de datos efectiva se ha convertido en un tema candente. Teniendo en cuenta las características de la plantación de huertos en filas y sombras causadas por características aleatorias dispersas, para mejorar la eficiencia energética de la red de sensores inalámbricos de huertos y prolongar la vida útil de la red, proponemos un algoritmo mejorado de enrutamiento jerárquico de agrupamiento basado en cadenas (ICCHR) basado en el algoritmo de LIXIVIACIÓN. El algoritmo ICCHR investiga la formación de grupos, la elección de la cabeza del grupo, la formación de la cadena, así como el proceso de transmisión de datos, y además se simula con los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH a través de MATLAB. Los resultados de la simulación muestran que para BS en (50, 175), desde el punto de vista de la métrica de muerte de todos los nodos sensores, la vida útil de la red para el algoritmo ICCHR se prolonga aproximadamente 3.29, 8.78, 35.53 y 43.11% en comparación con los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH. El consumo medio de energía por ronda del algoritmo ICCHR es inferior a los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH en aproximadamente 4,73, 9,04, 35,60 y 43,31%. Esta investigación puede proporcionar referencias teóricas para las redes inalámbricas del entorno complejo del huerto. Les nœuds de réseau de capteurs sans fil ont une énergie limitée, comment utiliser efficacement une énergie limitée pour réaliser une transmission de données efficace est devenu un sujet brûlant. Compte tenu des caractéristiques de la plantation de vergers en rangées et à l'ombre causées par des caractéristiques aléatoires clairsemées, afin d'améliorer l'efficacité énergétique du réseau de capteurs sans fil du verger et de prolonger la durée de vie du réseau, nous proposons un algorithme amélioré de routage hiérarchique en grappe basé sur la chaîne (ICCHR) basé sur l'algorithme de LIXIVIATION. L'algorithme ICCHR étudie la formation de grappes, l'élection de la tête de grappe, la formation de la chaîne ainsi que le processus de transmission de données, et est ensuite simulé avec les algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH via Matlab. Les résultats de simulation montrent que pour BS à (50, 175), du point de vue de toutes les métriques de mort des nœuds du capteur, la durée de vie du réseau pour l'algorithme ICCHR prolonge d'environ 3,29, 8,78, 35,53 et 43,11% par rapport aux algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH. La consommation d'énergie moyenne par tour de l'algorithme ICCHR est inférieure à celle des algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH d'environ 4,73, 9,04, 35,60 et 43,31 %. Cette recherche peut fournir des références théoriques pour le réseau sans fil de l'environnement complexe du verger. Wireless sensor network nodes have limited energy, how to employ limited energy efficiently to realize effective data transmission has become a hot topic. Considering the characteristics of orchard planting in rows and shade caused by sparse random features, to improve energy efficiency of the orchard wireless sensor network and prolong network lifetime, we propose an improved chain-based clustering hierarchical routing (ICCHR) algorithm based on LEACH algorithm. The ICCHR algorithm investigates the formation of clusters, cluster head election, chain formation as well as the data transmission process, and further simulated with E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms through MATLAB. The simulation results show that for BS at (50, 175), from the point of view of all sensor nodes death metric, the network lifetime for ICCHR algorithm prolongs about 3.29, 8.78, 35.53, and 43.11% compared with E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms. The average energy consumption per round of the ICCHR algorithm is lower than E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms about 4.73, 9.04, 35.60, and 43.31%. This research can provide theoretical references for the orchard complex environment wireless networking. تتمتع عقد شبكة المستشعرات اللاسلكية بطاقة محدودة، وأصبحت كيفية استخدام الطاقة المحدودة بكفاءة لتحقيق نقل البيانات الفعال موضوعًا ساخنًا. بالنظر إلى خصائص زراعة البساتين في الصفوف والظل الناجم عن الميزات العشوائية المتفرقة، لتحسين كفاءة استخدام الطاقة لشبكة استشعار البساتين اللاسلكية وإطالة عمر الشبكة، نقترح خوارزمية محسنة للتوجيه الهرمي للتجميع القائم على السلسلة (ICCHR) بناءً على خوارزمية الرشح. تبحث خوارزمية المركز الدولي لحقوق الإنسان في تشكيل المجموعات واختيار رؤساء المجموعات وتشكيل السلسلة بالإضافة إلى عملية نقل البيانات، وتمت محاكاتها بشكل أكبر باستخدام خوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH من خلال MATLAB. تظهر نتائج المحاكاة أنه بالنسبة لـ BS عند (50، 175)، من وجهة نظر جميع مقاييس موت عقد المستشعرات، فإن عمر الشبكة لخوارزمية ICCHR يمتد إلى حوالي 3.29 و 8.78 و 35.53 و 43.11 ٪ مقارنة بخوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH. متوسط استهلاك الطاقة لكل جولة من خوارزميات المركز الدولي لحقوق الإنسان أقل من خوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH حوالي 4.73 و 9.04 و 35.60 و 43.31 ٪. يمكن أن يوفر هذا البحث مراجع نظرية لبيئة البستان المعقدة للشبكات اللاسلكية.

Abstract System-level dynamic models of power plants are valuable tools for the assessment and prediction of plant performance, decisions on the design configuration, and the tuning of operating procedures and control strategies. In this work, the development of an integrated power plant model is presented. This model is validated against steady-state data from a subcritical power plant with reheat and regenerative cycles. The coal-fired power plant model studied has nominal power generation of 605 MW and efficiency of 38.3%. Traditional, regulatory control architectures are incorporated into and tuned with the dynamic power plant model. Dynamic simulation shows that the plant model is stable for sudden changes in coal load, and the controllers are able to maintain the controlled variables at their set points. In this two-part publication, we present the complete workflow of data collection, model development and validation, control tuning, dynamic optimization formulation and solution, and supervisory control architecture for a coal-fired subcritical power plant. Part I focuses on elements of model development and analysis, illustrating the advantages of acausal, object-oriented modeling in power plant simulation. Part II illustrates the use of this model for efficiency optimization under transient part-load operation.

In the current situation with the unprecedented deployment of clean technologies for electricity generation, it is natural to expect that storage will play an important role in electricity networks. This paper provides a qualitative methodology to select the appropriate technology or mix of technologies for different applications. The multiple comparisons according to different characteristics distinguish this paper from others about energy storage systems. Firstly, the different technologies available for energy storage, as discussed in the literature, are described and compared. The characteristics of the technologies are explained, including their current availability. In order to gain a better perspective, availability is cross-compared with maturity level. Moreover, information such as ratings, energy density, durability and costs is provided in table and graphic format for a straightforward comparison. Additionally, the different electric grid applications of energy storage technologies are described and categorised. For each of the categories, we describe the available technologies, both mature and potential. Finally, methods for connecting storage technologies are discussed.

Based on an extensive literature review and research interviews of energy experts, this article asks: what are the remaining impediments to clean energy systems and how can a Post-Kyoto Protocol climate framework be designed to overcome them? The article begins by exploring commercially available 'clean' energy systems and practices relating to energy end-use and infrastructure, energy supply, carbon capture and storage, and non-CO2 related greenhouse gas emissions. The article then examines a selection of persistent financial, market, information and intellectual property barriers. Lastly, it articulates the implication of these barriers for the design of future national and international climate change policies.

Considerable interest is being shown in using biochar production from waste biomass with a variety of disciplines to address the most pressing environmental challenges. Biochar produced by the thermal decomposition of biomass under oxygen-limited conditions is gaining popularity as a low-cost amendment for agro-ecosystems. The efficiency of biochar formation is affected by temperature, heating rate, feedstock type, particle size and reactor conditions. Properties such as pH, surface area and ash content of produced biochar increases with increasing temperatures. Biochar produced at lower heating rates may have high porosity and be beneficial for morphological changes in the soil. Biochar can help to enhance soil health and fertility as well as improve agricultural yield. As a result, biochar can assist in increasing food security by promoting sustainable agricultural systems and preserving an eco-friendly environment. Biochar is also widely being used as a sorbent for organic and inorganic pollutants, owing to its large surface area, allowing it to be immobilized from soil with ease. The functional groups and charges present on the surface of biochar play an important role in pollutants removal. This review focuses on the mechanisms of biochar production using different waste materials as a feed stock, factors that influence biochar quality as well as application of biochar in agricultural soil and their reclamation as well. This article also discusses knowledge gaps and future perspectives in the field of biochar-based toxic-pollution remediation.

Massive adoptions of combined heat and power (CHP) units necessitate the coordinated operation of power system and district heating system (DHS). Exploiting the reconfigurable property of district heating networks (DHNs) provides a cost-effective solution to enhance the flexibility of the power system by redistributing heat loads in DHS. In this paper, a unit commitment considering combined electricity and reconfigurable heating network (UC-CERHN) is proposed to coordinate the day-ahead scheduling of power system and DHS. The DHS is formulated as a nonlinear and mixed-integer model with considering the reconfigurable DHN. Also, an auxiliary energy flow variable is introduced in the formed DHS model to make the commitment problem tractable, where the computational burdens are significantly reduced. Extensive case studies are presented to validate the effectiveness of the approximated model and illustrate the potential benefits of the proposed method with respect to congestion management and wind power accommodation. (Corresponding author:Hongbin Sun)

SunPower Corp. describes its research to develop low-cost, next-generation SunPower modules with 30-year warranties and at least 50% higher energy production per area relative to today's typical multicrystalline Si modules.