Search Results (8)

Pansharpening is a critical technique in remote sensing, particularly in ecological and environmental monitoring, where it is used to integrate panchromatic (PAN) and multispectral (MS) images. This technique plays a vital role in assessing environmental changes, monitoring biodiversity, and supporting conservation efforts. While many current pansharpening methods primarily rely on PAN images, they often overlook the distinct characteristics of MS images and the cross-modal relationships between them. To address this limitation, the paper presents a Dual-Stream Cross-modality Fusion Network (DCMFN), designed to offer reliable data support for environmental impact assessment, ecological monitoring, and material optimization in nanotechnology. The proposed network utilizes an attention mechanism to extract features from both PAN and MS images individually. Additionally, a Cross-Modality Feature Fusion Module (CMFFM) is introduced to capture the complex interrelationships between PAN and MS images, enhancing the reconstruction quality of pansharpened images. This method not only boosts the spatial resolution but also maintains the richness of multispectral information. Through extensive experiments, the DCMFN demonstrates superior performance over existing methods on three remote sensing datasets, excelling in both objective evaluation metrics and visual quality. Full article

Due to the difference in output characteristics between the line-commutated converter-based high-voltage direct current (LCC-HVDC) and voltage-source converter-based high-voltage direct current (VSC-HVDC), the hybrid multi-infeed high-voltage direct current (HMIDC) presents complex coupling characteristics. As the AC side is disturbed, the commutation failure (CF) occurring on the LCC side is the main factor threatening the safe operation of the system. In this paper, the simplified equivalent network model of HMIDC is established by analyzing the output characteristics of VSC and LCC. Hereafter, based on the derived model and the control system of LCC-HVDC, the dynamic equations of the extinction angle are deduced. Consequently, by applying the phase portrait method, the causes of CF occurring in the HMIDC system as well as the impacts of control parameters on the transient stability are revealed. Furthermore, the stabilization boundaries for the reference value of the DC voltage are obtained via the above analysis. Finally, the theoretical analysis is verified by the simulations in the PSCAD/EMTDC. Full article

Accurate Remaining Useful Life (RUL) prediction of lithium batteries is crucial for enhancing their performance and extending their lifespan. Existing studies focus on continuous or relatively sparse datasets; however, continuous and complete datasets are rarely available in practical applications due to missing or inaccessible data. This study attempts to achieve the prediction of lithium battery RUL using random sparse data from only 10 data points, aligning more closely with practical industrial scenarios. Furthermore, we introduce the application of a Flexible Parallel Neural Network (FPNN) for the first time in predicting the RUL of lithium batteries. By combining these two approaches, our tests on the MIT dataset show that by randomly downsampling 10 points per cycle from 10 cycles, we can reconstruct new meaningful features and achieve a Mean Absolute Percentage Error (MAPE) of 2.36% in predicting the RUL. When the input data are limited to the first 10 cycles using the dataset constructed from random downsampling and the FPNN, the predicted RUL MAPE is 0.75%. The method proposed in this study offers an accurate, adaptable, and comprehensible new solution for predicting the RUL of lithium batteries, paving a new research path in the field of battery health monitoring. Full article

Medical images contain complex information, and the automated analysis of medical images can greatly assist doctors in clinical decision making. Therefore, the automatic segmentation of medical images has become a hot research topic in recent years. In this study, a novel architecture called a contoured convolutional transformer (CCTrans) network is proposed to solve the segmentation problem. A dual convolutional transformer block and a contoured detection module are designed, which integrate local and global contexts to establish reliable relational connections. Multi-scale features are effectively utilized to enhance semantic feature understanding. The dice similarity coefficient (DSC) is employed to evaluate experimental performance. Two public datasets with two different modalities are chosen as the experimental datasets. Our proposed method achieved an average DSC of 83.97% on a synapse dataset (abdominal multi-organ CT) and 92.15% on an ACDC dataset (cardiac MRI). Especially for the segmentation of small and complex organs, our proposed model achieves better segmentation results than other advanced approaches. Our experiments demonstrate the effectiveness and robustness of the novel method and its potential for real-world applications. The proposed CCTrans network offers a universal solution with which to achieve precise medical image segmentation. Full article

In this work, we prepared thermoplastic silicone rubber (TPSiV) by dynamically vulcanizing different relative proportions of methyl vinyl silicone rubber (MVSR), styrene ethylene butene styrene block copolymer (SEBS), and styrene butadiene styrene block copolymer (SBS). The compatibility and distribution of the MVSR phase and SEBS/SBS phase were qualitatively characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) tests on TPSiV. Subsequently, the backscattered electron signal image was analyzed using a colorimeter, and it was found that the size of the interface layer between the MVSR phase and the SEBS-SBS phase could be quantitatively characterized. This method overcomes the defect of the etching method, which cannot quantitatively analyze the size of the compatible layer between the two polymers. The final experiment proved that the two phases in TPSiV exhibited a “sea-island” structure, in which the MVSR phase acted as a dispersed phase in the SEBS-SBS phase. In addition, the addition of the silane coupling agent KH-907 (γ-isocyanatopropyltriethoxysilane) improved the mechanical properties of TPSiV, increasing the tensile strength by about 40% and the elongation at break by 30%. The permanent tensile deformation increase rate was about 15%. Through the quantitative measurement of the compatible layer, it was found that KH-907 could increase the thickness of the interface layer between the MVSR phase and the SEBS-SBS phase by more than 30%, which explained why the silane coupling agent KH-907 improved the mechanical properties of TPSiV at the micro level. Full article

Flight Maneuver Recognition (FMR) refers to the automatic recognition of a series of aircraft flight patterns and is a key technology in many fields. The chaotic nature of its input data and the professional complexity of the identification process make it difficult and expensive to identify, and none of the existing models have general generalization capabilities. A general framework is proposed in this paper, which can be used for all kinds of flight tasks, independent of the aircraft type. We first preprocessed the raw data with unsupervised clustering method, segmented it into maneuver sequences, then reconstructed the sequences in phase space, calculated their approximate entropy, quantitatively characterized the sequence complexity, and distinguished the flight maneuvers. Experiments on a real flight training dataset have shown that the framework can quickly and correctly identify various flight maneuvers for multiple aircraft types with minimal human intervention. Full article

University campus tourism is an important component and extension of urban tourism. The campus landscapes at universities act as major reflections of the interaction between regional natural and humanistic environments and initiate a strong visual perception or sensory feelings of the campus, which play a positive guiding role in campus tourism resource development. In order to better understand the role of landscapes in campus tourism, the Wangjiang Campus of Sichuan University was selected as the study area. Campus landscapes under the comprehensive influence of natural and humanistic environments were studied based on three different multi-level (scale) perspectives including: (i) point scale, (ii) line scale and (iii) plane scale, as well as different research themes comprising: (i) landscapes of buildings and vegetation, (ii) color landscapes, (iii) landscapes of campus space utilization, and (iv) thermal landscapes. The results show that the Wangjiang Campus landscapes have strong environmental natural landscape components linked with strong humanistic landscapes, which may provide lively, positive and relaxed visual feelings to tourists in the form of affirmative landscape services. The formation and development of the campus landscapes are affected by the geographic environments and campus culture, and it is conducive to the formation of unique campus genius loci. Nowadays, the landscapes of Wangjiang Campus have become a distinctive visiting card of campus tourism. This study would be helpful in better understating of the campus landscapes using new perspectives, as well as could be used as references for the development of university-campus-tourism. Full article

Polyborosiloxane gel (PBS-gel) with shear hardening properties was prepared by cross-linking boric acid and hydroxyl-terminated polydimethylsiloxane through B–O–Si dynamic covalent bonding. The prepared PBS gel was mixed with methyl vinyl silicone rubber (MVQ), and a benzoyl peroxide (BPO) cross-linking agent was added to vulcanize the silicone rubber. At the same time, the gel molecules were co-vulcanizing with MVQ to produce molecular cross-linking. The effects of PBS-gel on the damping properties of silicone rubber were analyzed by dynamic rheological test, Fourier transform infrared spectroscopy and dynamic mechanical analysis. The results demonstrated that the damping performance of MVQ/PBS rubber is greatly improved and the rubber has a tanδ > 0.3 in the range of −25~125 °C. The shear-hardening gel is uniformly dispersed in the system, due to the combined action of covalent bonds and intermolecular forces, which act as an active molecular chain that can efficiently dissipate and transfer energy inside the silicone rubber. Full article