Ultrafine WC-based cemented carbides with 10 wt.%AlxCoCrCuFeNi high-entropy alloy (HEA) binders were fabricated by spark plasma sintering, and the effects of HEA binders on the densification behavior of the WC-HEA cem...
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Ultrafine WC-based cemented carbides with 10 wt.%AlxCoCrCuFeNi high-entropy alloy (HEA) binders were fabricated by spark plasma sintering, and the effects of HEA binders on the densification behavior of the WC-HEA cemented carbides were studied. The densification of the WC-HEA cemented carbide, as well as traditional WC-Co, can be divided into the slow densification stage, rapid densification stage, and final densification stage. The densification behavior of the WC-HEA cemented carbides largely depends on the performance of the HEA binder during the SPS process. The sluggish diffusion effect of HEA weakens the diffusion of W atom on the powder particle surface and inhibits the growth of WC grain. Consequently, the disappearance of pores in the sintered compact is hindered, which leads to a low relative density of the WC-HEA cemented carbide. With the increase of Al content, the inhibitory effect of the AlxCoCrCuFeNi binder on the growth of WC grain is suppressed, and an Al-containing phase with a low melting point is more likely to form. Therefore, the relative density of the WC-10 wt.%AlxCoCrCuFeNi cemented carbide raises linearly with increasing Al content of the HEA binder.
Deep learning models have gained significant attention and application in recent years to improve the accuracy and efficiency of industrial time series prediction. However, the dynamic changes in industrial processes ...
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Deep learning models have gained significant attention and application in recent years to improve the accuracy and efficiency of industrial time series prediction. However, the dynamic changes in industrial processes present a key challenge for data-driven models. Specifically, the performance of deployed models deteriorates over time and fails to adapt to new operating conditions. Currently, two common update methods exist: Retraining the model using historical and new operating data, which incurs high computation and storage costs, or incrementally fine-tuning the model solely using new data, which leads to catastrophic forgetting of learned patterns. To address these issues, this article proposes an adaptive continual learning method for nonstationary industrial time series prediction. Our approach tackles the problems by hint-based network parameter learning to retain the dark knowledge from previous tasks and avoid catastrophic forgetting of accumulated knowledge. In addition, we design a soft buffer to aid memory and learning of key patterns under the current operating condition. Lastly, a time-sensitive activation function is proposed to endow the neural network with time-evolving properties, thereby enhancing the model's generalization ability. Compared with other update methods and different continual learning methods, the superiority of our method is validated on solar power generation data and real data of grinding and grading process.
Two new 3,8,13-trisubstituted triazatruxene derivatives containing different imidazole-derived moieties, 3,8,13TPI-TAT and 3,8,13-TTPI-TAT, were successfully synthesized by grafting different imidazole-derived moietie...
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Two new 3,8,13-trisubstituted triazatruxene derivatives containing different imidazole-derived moieties, 3,8,13TPI-TAT and 3,8,13-TTPI-TAT, were successfully synthesized by grafting different imidazole-derived moieties (phenanthroimidazole (PI) and 1,4,5-triphenylimidazole (TPI)) onto the 3,8,13-positions of a triazatruxene (TAT) core, and characterized by NMR (1H and 13C), high resolution mass spectrometry. Using the already reported 3,8,13-TBI-TAT as a comparison, the thermal stability, photophysical and electrochemical properties of these compounds were comparatively investigated to reveal the effects of different imidazole-derived groups on the luminescence properties of the compounds. The doped devices with a structure of ITO/PEDOT:PSS (45 nm)/ PVK:PBD (7:3, wt%):TAT compounds (x wt%) (30 nm)/TPBi (20 nm)/Liq (2 nm)/Al (150 nm) and non-doped devices were fabricated by solution-processed the emitting layers to investigate their electroluminescence (EL) performances, in which the devices of the diphenylimidazole substituted compound (3,8,13-TDPI-TAT) showed the best EL performances compared with that of the other two compounds. The doped devices of 3,8,13-TTPITAT exhibited a maximum luminance (Lmax) of 402 cd/m2 and a maximum external quantum efficiency (EQEmax) of 0.72 %, while its non-doped devices showed Lmax of 500 cd/m2 and the EQEmax of 1.43 %. It has important potential significance for the further design and synthesis of TAT derivatives with good charge transport and high EQE.
Segmentation of cell nuclei from three-dimensional (3D) volumetric fluorescence microscopy images is crucial for biological and clinical analyses. In recent years, convolutional neural networks have become the reliabl...
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Segmentation of cell nuclei from three-dimensional (3D) volumetric fluorescence microscopy images is crucial for biological and clinical analyses. In recent years, convolutional neural networks have become the reliable 3D medical image segmentation standard. However, convolutional layers are limited by their finite receptive fields and weight-sharing mechanisms. Consequently, they struggle to effectively model long-range dependencies and spatial correlations, which may lead to inadequate nuclei segmentation. Moreover, the diversity in nuclear appearance and density poses additional challenges. This work proposes a lightweight multi-layer deep aggregation network, MLDA-Net, incorporating Wide Receptive Field Attention (WRFA). This module effectively simulates the large receptive field generated by self-attention in the Swin Transformer while requiring fewer model parameters. This design implements an extended global sensory field that enhances the ability to capture a wide range of spatial information. In addition, the multiple cross-attention (MCA) module in MLDA-Net enhances the output features of different resolutions from the encoder while maintaining global effectiveness. The Multi-Path Aggregation Feature Pyramid Network (MAFPN) receives multi-scale outputs from the MCA module, generating a robust hierarchical feature pyramid for the final prediction. MLDA-Net outperforms state-of-the-art networks, including 3DU-Net, nnFormer, UNETR, SwinUNETR, and 3DUXNET, on the 3D volumetric datasets NucMM and MitoEM. It achieves average performance improvements of 4% to 7% in F1 score, MIoU, and PQ metrics, thereby establishing new benchmark results.
Inspired by the information transmission method of electrical signals in the biological impulse nervous system, a new variant of the spiking neural P systems, called spiking neural P systems with polarizations (PSN P ...
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In recent years, advancements in electrification, intelligent connectivity, and autonomous driving have made functional safety, particularly the vehicle-level controllability, a critical research focus. Although the I...
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Knowledge tracing (KT) aims to dynamically model learners' evolving knowledge states based on their historical learning records, playing a vital role in online education systems. Most existing KT methods learn the...
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Knowledge tracing (KT) aims to dynamically model learners' evolving knowledge states based on their historical learning records, playing a vital role in online education systems. Most existing KT methods learn the knowledge states as a transition pattern from the previous exercise to the next one, treating learners' entire learning records as continuous and uniformly distributed. However, we argue that actual learning records can be divided into distinct shorter sessions. To this end, we propose a novel KT model called Fine-grained Session Modeling for Knowledge Tracing (FSM4KT), which is designed to capture learners' knowledge state changes with finer granularity. In particular, we first divide learners' extensive historical learning records into shorter sessions from either temporal or knowledge concept-related perspective. Subsequently, a dedicated designed session-based knowledge proficiency modeling component is presented, which figures out intra-session and inter-session fine-grained interaction dependencies and knowledge state changes. Moreover, a global knowledge proficiency modeling component is introduced to holistically model learners' knowledge states. Extensive experimental results on three real-world datasets demonstrate that FSM4KT outperforms most of the current baseline methods, thus proving the effectiveness of FSM4KT.
Adverse weather conditions significantly impact the machine vision perception of unmanned platforms such as drones and autonomous vehicles. Therefore, restoring and enhancing images affected by these conditions is cru...
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Adverse weather conditions significantly impact the machine vision perception of unmanned platforms such as drones and autonomous vehicles. Therefore, restoring and enhancing images affected by these conditions is crucial. However, there is a lack of a comprehensive systematic review on the latest research progress in unified weather image restoration under all-in-one weather conditions and other factors. In this paper, we survey recent progress in various network architectures for multitask image restoration. Specifically, we review and compare different methods including, U-Net, GAN, Transformer, and U-Net/Transformer hybrids. Additionally, we evaluate publicly available datasets for single-task scenarios and compare the performance of these methods comprehensively, and analyze corresponding evaluation metrics. Based on these findings, we believe that Transformer and U-Net models are particularly promising for multi-task image restoration. Nevertheless, further research is needed to fully explore this area. Researchers can improve the image restoration effect from aspects such as data dynamic flow, encoder-decoder internal structure, etc. These insights contribute to advancing image acquisition technologies and addressing challenges in military image information retrieval, including military reconnaissance, terrain analysis, target identification, and battlefield surveillance.
Parallel decoding of backscatter improves communication throughput by enabling concurrent transmission of backscatter tags. In practical applications of parallel decoding, it is extremely difficult to distinguish coll...
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This paper studies the exponential stability and convergence rate analysis of continuous-time delay-difference systems. Firstly, stability and convergence rate analysis of delay-difference systems with both point dela...
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This paper studies the exponential stability and convergence rate analysis of continuous-time delay-difference systems. Firstly, stability and convergence rate analysis of delay-difference systems with both point delays and distributed delays having exponential integral kernels are studied by using the weighted Lyapunov-Krasovskii functionals (LKFs) approach and the state transformation approach, respectively. Different sufficient stability conditions expressed by linear matrix inequalities (LMIs) are presented. Secondly, as a particular case, LMIs based conditions and spectral radius based conditions are given to ensure the exponential stability with a guaranteed convergence rate for delay-difference systems with both point delays and distributed delays having constant integral kernels, respectively. Finally, numerical examples illustrate the effectiveness of the obtained results.
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