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Planar magnetic components have been widely used in high-density power converters and are suitable for various topologies. The application of planar inductors in LLC resonant converters can lead to parasitic capacitance, which causes current ringing and results in EMI issues. To mitigate the impact of current ringing, the parasitic capacitance of the planar inductor needs to be reduced. This paper proposes a new six-turn interleaved winding design. Compared to the previous four-turn interleaved winding design, it maintains low parasitic capacitance while positioning both the input and output terminals of the inductor on the outer turn, further enhancing the integration of high-density power converters. The parasitic capacitance was calculated using theoretical methods and verified through finite element simulations. Experimental validation was conducted using an LLC resonant converter test platform. Compared to the previous four-turn interleaved winding design, the new six-turn interleaved winding design satisfies both the input and output terminals, using an outer turn configuration. Additionally, the new design exhibits reduced parasitic capacitance and is suitable for use in LLC resonant converters, where it also minimizes current ringing. [ABSTRACT FROM AUTHOR]

Traditional visual detection methods that employ image data are often unstable due to environmental influences like lighting conditions. However, microfiber spectrometers are capable of capturing the specific wavelength characteristics of tail coal suspensions, effectively circumventing the instability caused by lighting variations. Utilizing spectral analysis techniques for detecting ash content in tail coal appears promising as a more stable method of indirect ash detection. In this context, this paper proposes a rapid detection method for the coal ash content in tailings suspensions based on absorption spectra and deep feature extraction. Initially, a preprocessing method, the inverse time weight function (ITWF), is presented, focusing on the intrinsic connection between the sedimentation phenomena of samples. This enables the model to learn and retain spectral time memory features, thereby enhancing its analytical capabilities. To better capture the spectral characteristics of tail coal suspensions, we designed the DSFN (DeepSpectraFusionNet) model. This model has an MSCR (multi-scale convolutional residual) module, addressing the conventional models' oversight of the strong correlation between adjacent wavelengths in the spectrum. This facilitates the extraction of relative positional information. Additionally, to uncover potential temporal relationships in sedimentation, we propose a CLSM-CS (convolutional long-short memory with candidate states) module, designed to strengthen the capturing of local information and sequential memory. Ultimately, the method employs a fused convolutional deep classifier to integrate and reconstruct both temporal memory and positional features. This results in a model that effectively correlates the ash content of suspensions with their absorption spectral characteristics. Experimental results confirmed that the proposed model achieved an accuracy of 80.65%, an F1-score of 80.45%, a precision of 83.43%, and a recall of 80.65%. These results outperformed recent coal recognition models and classical temporal models, meeting the high standards required for industrial on-site ash detection tasks. [ABSTRACT FROM AUTHOR]

The free energy principle and its corollary, the active inference framework, serve as theoretical foundations in the domain of neuroscience, explaining the genesis of intelligent behavior. This principle states that the processes of perception, learning, and decision making—within an agent—are all driven by the objective of "minimizing free energy," evincing the following behaviors: learning and employing a generative model of the environment to interpret observations, thereby achieving perception, and selecting actions to maintain a stable preferred state and minimize the uncertainty about the environment, thereby achieving decision making. This fundamental principle can be used to explain how the brain processes perceptual information, learns about the environment, and selects actions. Two pivotal tenets are that the agent employs a generative model for perception and planning and that interaction with the world (and other agents) enhances the performance of the generative model and augments perception. With the evolution of control theory and deep learning tools, agents based on the FEP have been instantiated in various ways across different domains, guiding the design of a multitude of generative models and decision-making algorithms. This letter first introduces the basic concepts of the FEP, followed by its historical development and connections with other theories of intelligence, and then delves into the specific application of the FEP to perception and decision making, encompassing both low-dimensional simple situations and high-dimensional complex situations. It compares the FEP with model-based reinforcement learning to show that the FEP provides a better objective function. We illustrate this using numerical studies of Dreamer3 by adding expected information gain into the standard objective function. In a complementary fashion, existing reinforcement learning, and deep learning algorithms can also help implement the FEP-based agents. Finally, we discuss the various capabilities that agents need to possess in complex environments and state that the FEP can aid agents in acquiring these capabilities. [ABSTRACT FROM AUTHOR]

To enhance the power density of LLC resonant converters, multilayer planar inductors are required. However, multilayer planar inductors have high parasitic capacitance, which may cause inductor current ringing in LLC resonant converters, leading to EMI problems. In this paper, it is found that by using interleaved winding inductors, compared with traditional winding inductors, the parasitic capacitance of multilayer planar inductors is reduced, which can reduce current ringing, without sacrificing power density and increasing manufacturing complexity. The method used to analyze current ringing is to establish an impedance model, and the parasitic capacitance of the interleaved winding inductors is verified by FEM simulations. The analysis is validated in an LLC resonant converter prototype. [ABSTRACT FROM AUTHOR]

Nuclear facilities generate large amounts of contaminated stainless steel metallic material during maintenance and decommissioning. As a new radioactive decontamination method, the self-brittle decontamination method has the advantages of fewer secondary contaminants and can be operated remotely mechanically. The addition of a certain amount of corrosive components to the self-brittlement composite decontaminant can achieve the dual function of self-brittlement and corrosion decontamination. The performance of the decontaminant was investigated by single-factor experiments using electrochemical tests, morphological observations, and weight loss tests. The results show that the decontaminant has good self-embrittlement. When the concentration of HCl is 2.50 mol/L, HNO3 is 3.50 mol/L, NaCl is 0.10 mol/L, and FeCl3 is 0.15 mol/L, the decontaminant is formulated to have the best corrosion and decontamination effect on stainless steel. The detergent will produce a uniform corrosion layer on the surface of stainless steel, and the average corrosion depth can reach 8.3268 μm. [ABSTRACT FROM AUTHOR]

Supporting high mobility is an important feature of the 6G mobile communication systems, which puts forward a great challenge for conventional orthogonal frequency division multiplexing (OFDM) systems due to the severe Doppler effects. Recently, orthogonal time frequency space (OTFS) has been proposed as a promising waveform for high-mobility scenarios, due to its excellent capability of exploiting delay-Doppler (DD) diversity to significantly improve the system performance. However, in multicell OTFS systems, intercell interference (ICI) is one of the major challenges, especially for cell-edge users (CEUs). In this article, the impacts of different types of interference on OTFS systems are first studied. Then, interference coordination and cooperative communications-based multicell OTFS systems are studied to overcome ICI, respectively. Next, simulation results are presented for the performance evaluation of these schemes. Finally, the main challenges are discussed and future research directions for multicell OTFS systems are highlighted. The performance evaluations demonstrate the effectiveness of interference coordination and cooperative communications on multicell OTFS systems. [ABSTRACT FROM AUTHOR]

The phase and microstructure of corrosion product formed on 2060-T8 Al–Li alloy have been investigated effectively by SEM and XRD after salt spray corrosion. It was found that the corrosion product growth rate can be divided into three stages: the main phases of corrosion product were Al2O3, Al(OH)3, and AlOOH phases; as the increasing of salt spray time, the phase angle of A12O3 shifts slightly to the left at 31.8°; and the phase angle of A12O3 first shifts to the left, then to the right at 38.6°. The formation and evolution model of salt spray droplet was built, and the formation mechanism of corrosion product was also analyzed. This alloy shows a sensitive corrosion performance to the salt spray environment. [ABSTRACT FROM AUTHOR]

The pulsed Gaussian beam in free space has been obtained and characterized. Use of a new initial value shows that such a beam can be expressed as a simple wave packet along with the complex time, which provides complete data on the spatial and temporal behaviors of the pulse. Couplings among the beam parameters in space and time are found to emerge on propagation of the pulse and involve two parts, one correlated with spot size and the other related to the wavefront.

Due to transmission of train control and dispatch commands, the ultra high reliability is required for railway wireless communication systems (RWCS). However, the quality of service (QoS) of RWCS is affected by external interference and jamming seriously in railway transportation. The external interference and jamming generated from intentional and/or unintentional sources can disturb the transmission of RWCS and be extremely dangerous for the trains’ safety. In this paper, a reconfigurable intelligent surface (RIS) approach is proposed to suppress the interference and jamming in RWCS. By taking the signal-to-interference-plus-noise (SINR) as the QoS metrics, the interference suppression problem with RIS is transformed into a maximizing receiving SINR problem. Two optimum solutions, which one is based on Charnes-Cooper transformation and the other is based on single linear programming, are provided. In order to deploy the RIS in RWCS practically, two low-complexity sub-optimum solutions, which one is to bypass the channel estimation for interference links and the other is to maximize the receiving desired power, are also discussed. The simulations results show that the RIS can be employed in RWCS with considerable anti-interference gain. [ABSTRACT FROM AUTHOR]

• The micro-nano structures were fabricated on Al-Li alloy by hydrothermal treatment. • The micro-nano structures were a mixture of AlOOH and Al(OH) 3 with good crystalline. • The micro-nano structures were leaf-like nano plates or flower-like structures. • The micro-nano structures change from (2 0 0) at 110 and 130 °C to (1 1 1) at 150 °C. • The micro-nano structures can be controlled by concentration of ST and temperature. The micro-nano structures were successfully fabricated on Al-Li alloy by adjusting the concentration of sodium formate and controlling the hydrothermal temperature though hydrothermal treatment. The growing directions and morphologies for micro-nano structures were studied. The results show the micro-nano structures were a mixture of AlOOH and Al(OH) 3 with good crystallinity, the intensity of diffraction peaks increases with the increase of sodium formate concentration, and the growing direction of micro-nano structure varied from (2 0 0) at 110 °C and 130 °C to (1 1 1) at 150 °C. The morphologies of the micro-nano structures exhibit patterned surface with overlapping leaf-like nano-plates at 110 °C and 130 °C, nordstandite is predominant, flower-like at 150 °C,aluminum oxide hydroxide is predominant.These findings directly demonstrate that the preferential growing direction and the morphologies of micro-nano structure has been confirmed with the concentration of sodium formate and the hydrothermal temperature. [ABSTRACT FROM AUTHOR]

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In this paper, we consider a downlink non-orthogonal multiple access (NOMA) enabled heterogeneous small cells network (HSCN), where the macro base station simultaneously communicates with multiple small cell base stations (SBSs) through wireless backhaul. In each small cell, users are grouped by NOMA bases and then served by their respective SBS. The proposed framework considers the realistic imperfect channel state information and quality of service requirements of users. The goal is to investigate an energy-efficient joint power, and bandwidth allocation scheme, which aims to maximize the energy efficiency (EE) of the small cells in downlink NOMA-HSCN constrained by the maximum transmit power and the minimum required data rate simultaneously. The optimization problem is non-convex due to the fractional objective function and non-convex constraint and thus challenging to obtain an exact solution efficiently. To this end, the joint optimization is first decomposed into two subproblems. Then, an iterative algorithm to solve the power optimization subproblem is proposed with guaranteed convergence. Furthermore, we derive a closed-form solution for the bandwidth allocation subproblem. Simulation results reveal that the effectiveness of the proposed schemes in terms of EE compared to the existing NOMA and the orthogonal multiple access schemes. [ABSTRACT FROM AUTHOR]

Background/Aims: Glycolysis, a multi-step enzymatic reaction, is considered to be the root of cancer development and progression. The aim of this study is to figure out which glycolysis enzyme participates in the progression of breast cancer and its possible mechanisms. Materials: We firstly screened out PGK1 by performing an RT-PCR array of glycolysis-related genes in three paired breast cancer samples, and further investigated PGK1 using TCGA and our own database. The effect and mechanism of PGK1 on cell invasion was further explored both in vitro and using patient samples. Results: PGK1 was most upregulated in T3N0 with distant metastases compared to those with no metastases. In the TCGA database, high PGK1 expression predicted poor overall survival (OS) in breast cancer and some other cancers (P< 0.001). In the validation cohort, high PGK1 expression was significantly correlated with larger tumor size (P=0.011) and advanced TNM stage (P=0.033), and PGK1 expression was an independent prognostic factor for OS and disease free survival (DFS) in both univariate and multivariate regression analyses (P< 0.05). Functional studies indicated that knockdown of PGK1 expression significantly inhibited invasion and reversed the epithelial-mesenchymal transition process in breast cancer cells (P< 0.05). Mechanistically, PGK1 increased HRE luciferase activity in a dose-dependent manner, while silencing PGK1 expression decreased HRE activity. Conclusion: High PGK1 expression was associated with poor prognosis in breast cancer, because PGK1 and HIF-1α formed a positive feed-forward loop and thus stimulated breast cancer progression and metastases. Based on these results, PGK1 may serve as a promising biomarker and target therapy for breast cancer. [ABSTRACT FROM AUTHOR]

Ultra-dense networks (UDNs) are the promising technology for the fifth-generation wireless networks and beyond to significantly boost network capacity and improve network coverage by exploiting spatial spectrum reuse through the deployment of massive base stations (BSs). In this paper, the fundamental tradeoffs of non-orthogonal multicast, multicast, and unicast in the UDN are studied, to understand the impact of network densitification on them and provide some insights on UDN deployment. Non-orthogonal multicast with imperfect channel estimation and successive interference cancellation is also investigated. To evaluate the performance, a tractable model for performance analysis is developed by using stochastic geometry, and then the analytical expressions for downlink signal-to-interference-plus-noise ratio coverage probability, spectrum efficiency, area traffic capacity, and energy efficiency are derived. The numerical results together with the Monte Carlo simulations are also provided. The results demonstrate that non-orthogonal multicast can further improve the performance of multicast and achieve higher spectrum efficiency, area traffic capacity, and energy efficiency than unicast from the low-to-high BS density regions, but suffers from inferior performance to unicast in the very high BS density region. The results also show that the non-orthogonal multicast and multicast exhibit different performance trends from unicast. [ABSTRACT FROM AUTHOR]

Non-orthogonal multiple-access (NOMA) with perfect successive interference cancellation is an emerging research topic in the future wireless communication systems. In this work, NOMA is applied to dual-hop relaying systems, where the signals are transmitted with the aid of either decode-and-forward (DF) or amplify-and-forward (AF) relay. Exact expressions for outage probability and ergodic capacity are derived over independent Rayleigh fading channels, and a tight upper bound for the outage probability of AF scheme is provided. Based on the analysis, we study forwarding strategy selection for both fixed and optimized power allocation. The presented simulations verify the accuracy of the analysis, and the efficiency of the proposed forwarding strategy. [ABSTRACT FROM AUTHOR]