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Abstract The innovation of this research was a holistic approach to the problem of linking the biometric characteristics of six energy plants species and the distribution of moisture along the shoot‘ height and determination of linear models of particle sizes in relation to the moisture. The median biometric parameters values for growth phases I and II were as follows: shoot weight: 63 g and 65 g; stalk weight: 45.1 g and 43.8 g; plant length: 1273 mm and 2157 mm; shoot centre of gravity: 698 mm and 968 mm; slenderness ratio 147 and 215, respectively. For big bluestem and Spartina pectinata the largest values were for slenderness ratio and for phase II amounted to 403 and 410, respectively but most other parameters were the smallest values. Regarding the shoots’ growth, the greatest influence was on the stalks by increasing their lengths more than their diameters. The highest difference in the plant length between harvest terms was observed for Spartina pectinata which increased from 793 mm to 2257 mm (by 185%). The lengths of the Jerusalem artichoke, miscanthus and big bluestem plants also significantly increased: from 1345 mm to 2920 mm (117%), 1214 mm to 2065 mm (70%) and 1064 mm to 1779 mm (67%), respectively. Positive correlation coefficient values between parameters (shoot weight, leaf weight, stalk weight and plant length) indicate that to characterize of plant shoots the shoot mass and plant slenderness could be used. The Rosin-Rammler function fit the chopped plan material size distribution data with an R 2 = 0.909–0.991. All the biomass particle sizes belonged to the “very poorly sorted” category (2.00 mm ≤ σ ig ≤ 4.00 mm), and the particle size distributions were “fine skewed” (0.1 ≤ GS is ≤ 0.3) and “mesokurtic” (0.90 ≤ K gs ≤ 1.11). For grasses relation of particle sizes vs. moisture for phase II (August for Spartina and big bluestem or October for miscanthus) was inverted to phase I (June) with slope coefficients −0.11 and 0.09, respectively. For leaf plants direction of the relation was preserved, wherein for phase II (all plants harvested in October) the growth dynamic was lower than for phase I and slope coefficients of the lines were 0.17 and 0.04, respectively. Moisture content of leafy plants was high, and its distribution along the shoots’ heights was different than that for grasses. Varied values of particle size and weight of plant components, together with the change in moisture along the height of the plants, will impact the diversity of the dynamic loads of elements and working units of forage harvesters and can be useful to explain these results.

ABSTRACTAn overview is given of an International Atomic Energy Agency Coordinated Research Project (CRP) on the treatment of irradiated graphite (i-graphite) to meet acceptance criteria for waste disposal. Graphite is a unique radioactive waste stream, with some quarter-million metric tons worldwide eventually needing to be disposed of. The CRP has involved 24 organizations from 10 Member States. Innovative and conventional methods for i-graphite characterization, retrieval, treatment and conditioning technologies have been explored in the course of this work, and offer a range of options for competent authorities in individual Member States to deploy according to local requirements and regulatory conditions.

Abstract This paper provides a forecast of electricity consumption in Cyprus up to the year 2030, based on econometric analysis of energy use as a function of macroeconomic variables, prices and weather conditions. If past trends continue electricity use is expected to triple in the coming 20–25 years, with the residential and commercial sectors increasing their already high shares in total consumption. Besides this reference scenario it was attempted to assess the impact of climate change on electricity use. According to official projections, the average temperature in the Eastern Mediterranean is expected to rise by about 1 °C by the year 2030. Using our econometrically estimated model, we calculated that electricity consumption in Cyprus may be about 2.9% higher in 2030 than in the reference scenario. This might lead to a welfare loss of 15 million Euros in 2020 and 45 million Euros in 2030; for the entire period 2008–2030 the present value of costs may exceed 200 million Euros (all expressed in constant Euros of 2007). Moreover, we assessed the additional peak electricity load requirements in the future because of climate change: extra load may amount to 65–75 Megawatts (MW) in the year 2020 and 85–95 MW in 2030.

Abstract Currently, the first generation of silicon solar cells is dominating the photovoltaic market. Silicon cells are produced by various methods, which employ either crystalline or multi-crystalline substrates. However, both these manufacturing processes are expensive and potentially harmful to the environment and health. One example of this is that the surface is given its texture in a highly corrosive water solution of nitric and hydrofluoric acid. Additionally, both the diffusion and manufacturing of p-n junction and of metal contacts are associated with very high temperatures. This prompted us in our search for cheaper and more environmental friendly technologies. In this work, we discuss the possibility of producing components of photovoltaic cells by employing atomic layer deposition and hydrothermal technologies. This does not require the use of hazardous chemicals and high temperatures. The maximum efficiency of zinc oxide/silicon solar cells is 14% and 10% for textured and planar structures, respectively. A environmentally-friendly and simple procedure is thus being proposed, which, together with its relative efficiency, makes it an attractive alternative to the present procedure.

The influence of voltage transformers on the operating conditions of the ground-fault protection systems of unit-connected generators excited by the ratio of 3rd harmonic voltages in the generator neutral and at the generator terminals was determined. An optimising analysis of these conditions with regard to the value of the voltage transformers feeding the protection system was carried out. Simulation tests were run for high-power unit-connected generators equipped with generator breakers with capacitance to ground. It was found that the optimisation of the voltage transformers ratio markedly improves the operating conditions of the protection and ensures 100% protection of the length of the stator winding.

Data Availability: The data that support the findings of this study are available from the corresponding author, C. Wen, upon reasonable request. ; Deep-learning-based fault diagnosis of wind turbine has played a significant role in advancing the renewable energy industry. However, the imbalanced data sampled by the supervisory control and data acquisition systems has led to low diagnosis accuracy. Additionally, deep neural networks can encounter issues like gradient vanishing and insufficient feature learning during backpropagation when the model is too deep. This article introduces a novel approach that is based on dynamic weight loss functions to modulate unbalanced data and improve diagnostic accuracy by focusing on misclassification of a small sample number. The proposed approach employs a 1D-CNN model and an ensemble-learning-based convolution neural network (EL-CNN) to enhance diversity of models and complementarity of feature learning. The EL-CNN model addresses the problem of local features being overlooked and provides more accurate results. The effectiveness of this proposed approach is well demonstrated through experimental cases on real wind turbine pitch system fault data. Two different networks using three different loss functions and three state-of-the-art fault diagnosis models are tested, demonstrating the EL-CNN model’s superiority. ; This work was supported in part by the European Union’s Horizon 2020 Research and Innovation Programme under Grant 820776 (INTEGRADDE), the Engineering and Physical Sciences Research Council (EPSRC) of the UK, the Royal Society of the UK, the Alexander von Humboldt Foundation of Germany, the BRIEF Award of Brunel University London, the National Natural Science Foundation of China under Grant 61973209, the Natural Science Foundation of Shanghai of China under Grant 20ZR1421200, and the Capacity Building Project of Shanghai Local Colleges and Universities of China under Grant 22010501100.

Char reactivity usually determines the overall efficiency of the entire gasification process, while the presence of the alkali and alkaline earth metals (AAEMs) has a catalytic effect on char gasification. In this study, the influence of inherent AAEMs in the gasification behaviour of char was investigated. The char sample was prepared through the pyrolysis of solid digestate derived from anaerobic co-digestion of silage and dairy cattle slurry. The raw char and HCl-washed char were characterized by elemental analyzer, ICP-OES, SEM and XRD to explore their structural changes. HCl-char loses weight in the temperature range of 440–620 °C, and the weight loss percentage is significantly higher than that of char. Ash content of char is reduced by half after a pickling process. AAEMs are largely removed after char acid pickling, resulting in an increase in activation energy of the gasification reaction and a decrease in gasification reactivity, resulting in the gasification reaction time of HCl-char longer than char. Water-soluble AAEM and ion-exchange AAEM affect the evolution of carbon structure, which directly lead to char reactivity during the gasification reaction. As the carbon is consumed, the carbon microcrystalline structure of the residual carbon tends to be ordered, resulting in fewer active free carbon sites for the gasification reaction. Kinetic analysis showed that the loss and deactivation of AAEMs after char acid washing increased the average activation energy E a by 115.76 KJ/mol compared with the original char.

This paper is focused on the energy performance of buildings containing massive exterior building envelope components. The effect of mass and insulation location on heating and cooling loads is analyzed for six characteristic wall configurations. Correlations between structural and dynamic thermal characteristics of walls are discussed. A simple one-room model of a building exposed to periodic temperature changes is analyzed to illustrate the effect of material configuration on the ability of a wall to dampen interior temperature swings. Whole-building dynamic modeling using DOE-2.1E is employed for the energy analysis of a one-story residential building with various exterior wall configurations for six different US climates. The best thermal performance is obtained when massive material layers are located at the inner side and directly exposed to the interior space.