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The evaporation process is vital in alumina production, with mother liquor concentration serving as a critical control parameter. To address the challenge of online detection, we propose the introduction of a soft measurement strategy. First, due to the significant fluctuations in the production process variables and inter-variable coupling, comprehensive grey correlation analysis and kernel principal component analysis are employed to reduce the input dimension and computational complexity of the data, enhancing the efficiency of the soft sensing model. The reduced robust least-squares support-vector machine (LSSVM), with its commendable predictive performance, is used for modeling and predicting the principal components. Concurrently, an improved Pattern Search-Differential Evolution (PS-DE) algorithm is proposed for optimizing the pivotal parameters of the LSSVM network. Lastly, on-site industrial data validation indicates that the new model offers superior tracking capabilities and heightened accuracy. It is deemed aptly suitable for the online detection of mother liquor concentration. [ABSTRACT FROM AUTHOR]

Capacitive power transfer (CPT) is an attractive wireless power transfer (WPT) technology and it has been widely studied in many applications. Symmetrical structures and high-order compensation networks are always produced as optimization results and common configurations for high-efficiency CPT systems. However, in space-limited scenarios, an asymmetric structure tends to be a better choice. The related large number of high-order asymmetric system parameters is a key problem in parameter design. In this study, a general parameter design method that is based on reactive power optimization is proposed for an electric field resonance-based CPT system with an asymmetric six-plate coupler. The reactive power in the compensation network was analyzed and optimized under the constraint of transferred power. With equal reactive power, the optimization complexity was significantly reduced and the optimized system parameters were provided. To validate the effectiveness of the proposed method, a 1 MHz, 3.2 kW asymmetric CPT protype with 100 mm gap distance was implemented. The results indicate that, with the optimized parameters, high system efficiency can be achieved when the system's volume is reduced. At the rated power, about 95% DC–DC overall efficiency was achieved through a 6-pF coupling capacitor. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) is more convenient and safer than conductive charging for power consumer electronics, biomedical devices, transportation systems, etc. Inductive power transfer is the most widely studied and commercialized WPT technique; however, capacitive power transfer (CPT) is becoming an attractive alternative, offering better misalignment tolerance and lower cost and weight. The electrical-field-resonance-based six-plate coupler system is one of the most typical configurations for high-performance CPT systems, but the associated large number of circuit parameters is always a critical issue for system design. In this article, a parameter optimization method is proposed for this topology. The ratio of the reactive power in the compensation network to the system transferred power is set as the main optimization goal. To solve the high-order optimization problem, a two-stage method is proposed to significantly reduce the optimization complexity while providing the optimized parameters of the whole system. To verify the effectiveness of this method, a 3-kW, 1-MHz CPT system with a 16-pF coupling capacitor is built. Both the simulation and experimental results show that the optimized parameters effectively improve the system efficiency, experimentally achieving 95.7% dc–dc overall efficiency under a 100-mm gap distance at the rated power. [ABSTRACT FROM AUTHOR]

Building energy consumption accounts for a large fraction of the total global energy usage, and considerable energy savings are expected to be achieved in this respect through residential electrical load monitoring. Due to the limitations on the practical implementation of in-depth and expensive monitoring systems, non-intrusive load monitoring (NILM) is becoming a hot topic. In this paper, an overview of the state of the art residential electrical load monitoring is presented. Different from previous reviews, the applications of load monitoring are particularly addressed, based on which, technical challenges of load monitoring techniques, including NILM, are identified and thoroughly discussed, together with possible developments and trends predicted from the authors' perspective. [ABSTRACT FROM AUTHOR]

Pentoxifylline exhibits complex functions with extensive pharmacological effects and is used therapeutically due to its therapeutic effects and rapid metabolism in the body, with no cumulative effects and few side effects. The present study investigated the effects of pentoxifylline on cerebral ischemia reperfusion-induced injury (IRI) through suppression of inflammation in rats. Hematoxylin and eosin staining was performed to evaluate the number of neurocytes, and ELISAs were applied to measure tumor necrosis factor-a, interleukin-6, malondialdehyde and superoxide dismutase activities. Treatment with pentoxifylline significantly recovered the cerebral ischemia reperfusion-induced neurological deficit score and cerebral infarct volume in rats. In addition, pentoxifylline treatment significantly reversed the cerebral ischemia reperfusion-induced interleukin-6, tumor necrosis factor-a, malondialdehyde and superoxide dismutase levels in vivo. Furthermore, pentoxifylline significantly inhibited cyclooxygenase-2 and inducible nitric oxide synthase mRNA and protein expression in cerebral IRI mice. Treatment with pentoxifylline also significantly suppressed the expression of cleaved caspase-3 and p38 mitogen-activated protein kinase (MAPK) protein in cerebral IRI mice. These results indicate that the protective effects of pentoxifylline on cerebral IRI may occur via the p38 MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

With the development of electric vehicles and consumer electronics, wireless power transfer (WPT) is becoming a popular technology. Recently, magnetic resonant coupling has been considered to be the most effective and attractive WPT approach, and the two-coil structure is the most widely used for magnetic resonant coupling. It has been recently reported that the system's energy efficiency can be improved by a three-coil structure. In this paper, the three-coil structure is compared with the two-coil structure based on circuit theory. Simplified circuit models of the two- and three-coil structures are proposed to give a more intuitive and comprehensive analysis of the energy efficiency differences between the two structures. With the simplified model, the condition for a three-coil structure obtaining higher energy efficiency over its two-coil counterpart is derived, and the analysis shows that the WPT system with higher energy efficiency within a wider range of loads can be achieved by properly designed three-coil systems. Additionally, it also shows that the three-coil system has the significant advantage of reducing the current stress and the electromagnetic field emission that is caused by misalignments. The theoretical analysis is confirmed by both simulation and experimental results. [ABSTRACT FROM AUTHOR]

To meet the future emission legislations, selective catalytic reduction aftertreatment system becomes a leading aftertreatment technique for heavy-duty diesel engines. In this article, a two-cell selective catalytic reduction model is first calibrated and verified on an experimental test bench. In order to regulate the ammonia coverage ratio in a proper range, an ammonia storage control is proposed based on the selective catalytic reduction model. The problem of NH3 slip during temperature rise is discussed and a corresponding perturbation injection control is proposed to buffer the sudden change in selective catalytic reduction ammonia storage capability. The NH3 slip control performance of the proposed strategy is experimentally validated in European Transient Cycle. [ABSTRACT FROM AUTHOR]

Wireless power transfer technology is being widely used in electric vehicle wireless-charging applications, and foreign object detection (FOD) is an important module that is needed to satisfy the transmission and safety requirements. FOD mostly includes two key parts: metal object detection (MOD) and living object detection (LOD), which should be implemented during the charging process. In this paper, equivalent circuit models of a metal object and a living object are proposed, and the FOD methods are reviewed and analyzed within a unified framework based on the proposed FOD models. A comparison of these detection methods and future challenges is also discussed. Based on these analyses, detection methods that employ an additional circuit for detection are recommended for FOD in electric vehicle wireless-charging applications. [ABSTRACT FROM AUTHOR]