bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of High and Low Temperature Performance of Titanium Zirconium Molybdenum Alloy and High Temperature Alloy Brazed Joint
Authors: Jian Yang , Jianyu Yuan , Wenwen Li , Yuchen Yang , Zihan Tu , Jintao Liu , Wenjiang Zou , Wei Mao , Yanlin Hu 
Published: October 2024

Abstract
Using niobium as the intermediate layer and gold nickel (Au82-Ni) filler metal, TZM alloy and high-temperature alloy GH3128 were brazed. The brazed specimens were subjected to 400 cycles of high and low temperature cycling tests at temperatures ranging from 650 °C ∼ 680 °C (high temperature) to -196 °C (low temperature) for 10 minutes seperately. Then the microstructure variation before and after the experiment were observed and the shear strength of the specimens were tested at room temperature for 50 cycles of 400 high and low temperature testing..
The results show that the microstructure of the transition zone at the brazing interface after brazing is uniform and dense, with good wettability with the substrate and no defects such as cracks. The solder and substrate undergo diffusion reactions, and the molybdenum alloy, niobium, and niobium, high-temperature alloy had each form diffusion layers, formed intermetallic compounds on the brazing surface.
After high and low temperature cycling, cracks exist in the braze seam between molybdenum alloy and niobium alloy. The cracking mode should be thermal fatigue based on the fracture morphology and phase analysis. The reasons of interface cracking are that due to different thermal expansion coefficients, low mutual solid solubility, and the formation of a large number of different types of intermetallic compounds, Mo and Nb materials have poor brazing compatibility and lower interface strength. Under cold and hot cycling conditions, brittle intermetallic compounds are prone to form crack source areas. As the number of cycles increases, the cracks gradually expand, ultimately leading to product leakage. In addition, the shear strength of brazed joints shows a decreasing trend with the increase of high and low temperature cycles in 400 high and low temperature tests.
Analysis of vortex induced vibration on the hundred-meter wind turbine blade based on CFD and FEM
Authors: Mao Zhongyu , Zhao Jing , Zhou Wenming , Qiao Yujun , Fan Zhenya 
Published: October 2024

Abstract
Along the development of wind turbine blade toward large size and light weight, the length of blade running-now has come to the level of hundred-meter, while the structure of blade trends to be flexible. During the shutdown conditions, blades are affected by wake vortex from different inflow speed and angle, which often induce blade vibration. It seriously affects the safety and service life of wind turbines, even may cause blade breakage accident. This paper focused on the vortex induced vibration on the hundred-meter wind turbine blade. Based on the Computational Fluid Dynamics (CFD) transient method, the wake flow field of three relative thickness aerofoils has been simulated under different inflow speed and angle. The distribution of vorticity has been compared. Based on the Fast Fourier Transform (FFT) method, the frequency of wake vortex has been analysed from the pressure pulsation, compared with the natural frequency of this hundred-meter blade calculated by the Finite Element Method (FEM). This result may be regarded as a simulation support to avoid vortex induced vibration of hundred-meter wind turbine blade.
Remaining Useful Life Prediction of Rolling Bearings Based on Time-Frequency Enhanced Transformer Model
Authors: Lin Chunyu , Luo Hongli , Wu Zhenpeng , Zhang Liangwei 
Published: October 2024

Abstract
Deep learning has achieved a lot of progress in predicting Remaining Useful Life (RUL). However, contemporary deep learning frameworks face inherent limitations, including constrained receptive fields, difficulties in capturing long-term dependencies, and singularities within the feature extraction domain. In response to these challenges, we propose a novel time-frequency enhanced Transformer model for predicting the remaining lifespan of rolling bearings. In this model, we utilize causal convolution operations to capture local features in the time-frequency domain and incorporate position encoding into the input signal. The time-frequency enhanced model exhibits end-to-end characteristics, feature fusion and selection can be performed without tedious feature extraction compared to existing methods. Furthermore, we introduce a custom Weighted Smooth Mean Squared Loss function to enhance the model’s prediction accuracy and interference resilience. In experiments, we comprehensively compare various advanced RUL prediction methods, with the results highlighting the superior performance and robust interference resistance of the time-frequency enhanced Transformer model in predicting the RUL of bearings.
Cloud removal in landsat images based on spatial-spectral-temporal random forests
Authors: Tang Yijie 
Published: October 2024

Abstract
The Landsat-8 Operational Land Imager (OLI), together with the Landsat-9 OLI2 sensors, provides important optical data for various applications. Due to frequent cloud cover, the obtained Landsat images always contain different degrees of spatial information loss. Although great efforts have been made to remove clouds in remote sensing images in recent decades, there still exists a large challenge, that is, the land cover changes between the target cloudy and the auxiliary cloud-free images, which limits greatly the accuracy of cloud removal. To cope with this issue, a spatial-spectral-temporal random forest (SSTRF) algorithm was proposed in this paper. The SSTRF model aims at removing clouds in Landsat images with the assistance of a remote sensing image with spatially complete cover from another satellite, that is, the 8-day MODIS surface reflectance product (MOD09A1). By compositing the valid data from 8 separate days, the MOD09A1 product has a great possibility to provide cloud-free land cover change information for the cloud removal of Landsat images. Through experiments with simulated and real clouds, SSTRF was demonstrated to produce greater accuracy than two benchmark cloud removal methods and has great potential to be applied to practical use.
Parametric indoor 3D reconstruction based on binary image feature point extraction
Authors: Gao Yuan 
Published: October 2024

Abstract
In recent years, with the rapid advancement of laser scanning technology, indoor 3D modeling technology has significantly developed, becoming a research hotspot in the field of 3D reconstruction. Addressing the issues of high complexity in decoding point cloud surfaces in traditional indoor reconstruction, this paper proposes an indoor 3D reconstruction method based on binary image feature point extraction. The method utilizes point cloud data for semantic segmentation of the indoor environment to accurately extract the ceiling area, which is then projected onto the XOY plane and converted into a binary image, thereby transforming the 3D problem into a 2D problem. Subsequently, key feature points are identified through feature point detection technology, and systematic model construction is carried out based on the sequence of these feature points and their associated parameters. This method effectively simplifies the complexity of traditional 3D modeling, achieving accurate and parametric indoor 3D reconstruction.
Simulation and fabrication of a 20 kHz single-beam transducer
Authors: Zhang Yifan , Liu Yun 
Published: October 2024

Abstract
With the vigorous development of underwater acoustic technology in China, underwater acoustic transducers are constantly moving towards broadband, low-frequency, and high-power directions. How to obtain piezoelectric transducers with lower frequencies is still a research direction that scholars from various countries are striving to study.
This article mainly studies and manufactures a 20 kHz single-beam piezoelectric transducer, using the classic Tonpilz transducer structure. Firstly, the Tonpilz transducer is theoretically analyzed using the classical equivalent circuit method. Secondly, the transducer is analyzed using ANSYS finite element analysis software to study the influence of piezoelectric ceramics on the frequency of the transducer, and the size of the piezoelectric ceramics is optimized to determine the size of the piezoelectric ceramic structure of the transducer. The working frequency of the transducer was calculated using software, and it was determined that the working frequency was approximately 20 kHz.
Application of UAV airborne LiDAR technology in highway engineering construction
Authors: Ding Jie , Chen Li 
Published: October 2024

Abstract
The airborne LiDAR technology of UAVs is an efficient and high-precision spatial information acquisition technology. This paper introduces the airborne LiDAR technology of UAV in detail and studies the application of airborne LiDAR technology of UAV in highway construction based on the sixth section of the Leibokahalo-Yongshan connection line of G4216 Yibin Xinshi to Panzhihua Section. Engineering application practice shows that this technology can solve the difficult problem of obtaining basic geographic information data, and verify the rationality of the scheme and the matching degree with the field environment. In addition, compared with traditional survey technology, the technology has obvious advantages in the construction of highways in complex terrain, which helps to improve the quality of survey and design.
Improved mangrove refined extraction method based on remote sensing intelligent extraction model
Authors: Gu Xianghui , Yang Xiaotong , Shi Zhizhou , Zhang Feng , Jiao Hongbo , Zhao Binru 
Published: October 2024

Abstract
Mangrove ecosystems are blue carbon ecosystems with important ecological and environmental significance. Refined monitoring of mangroves is a prerequisite for their management and protection, and remote sensing technology is an indispensable tool for timely and accurate monitoring of mangroves. However, the present methods for extracting mangroves from high-resolution images suffer from problems such as inaccurate boundaries, missing targets, and low accuracy for sparse mangroves. To address these challenges, a novel mangrove extraction method is employed, integrating DeepLabV3+ with the Convolutional Block Attention Module (CBAM). A multi-spectral dataset of mangroves has been established, using a long-time series of multi-source high-resolution images covering many provinces. This comprehensive dataset is subsequently applied to both the baseline model and an improved model for comparative assessment. In comparison with the baseline network, the improved network demonstrates superior performance in mangrove segmentation, exhibiting heightened accuracy, particularly in challenging areas such as the intricate edges and sparsely vegetated regions. The improved model is applied to GF-1 satellite images in the northern Beibu Gulf, yielding segmentation accuracy exceeding 95% when validated against ground truth measurement data. Our proposed methodology significantly contributes to the efficacious management and protection of mangrove ecosystems.
Removing thick clouds in landsat 8 OLI images with cloudy time-series auxiliary data
Authors: Wang Lanxing 
Published: October 2024

Abstract
Thick cloud occlusion severely limits the subsequent application of optical remote-sensing images. Existing mainstream cloud removal methods often use cloud-free homologous temporal images to provide auxiliary information. However, due to the limitation of cloud occlusion and satellite revisit cycle, the time interval between the cloud-free auxiliary image and the target cloudy image is often too large, and the possible land cover changes during the period increase the uncertainty of effective information on the auxiliary images. In this case, more accurate reconstructions may be obtained by using temporally closer and partially cloud-contaminated images. In this paper, a deep network, convLSTM, is developed for cloud removal (i.e., CR-convLSTM), which makes full use of the complementary effective information on partially cloud-contaminated time-series images. Experiments based on simulated clouds indicated that CR-convLSTM can obtain more accurate predictions than the classical cloud removal method MNSPI. CR-convLSTM is an effective cloud removal method with high computational efficiency while ensuring predicting accuracy.
Spatio-temporal grid-based storage method for aerospace operation and control data
Authors: Li Shuo , Chen Jinyong , Peng Huixiang , Wang Gang , Miao Shaobo 
Published: October 2024

Abstract
The current aerospace operation and control data system has problems such as difficult integration organization and difficult data retrieval in terms of mission planning efficiency, which limits the development of satellite operation and control systems. This paper is oriented to the organization and management of aerospace operation and control data, according to the nature of the current big data indexing model. Based on the principle of earth dissection, we aim to design a grid that can be indexed. First of all, the Earth is dissected to form a hierarchical and uniformly distributed global geographic grid, and then the formed grid is encoded to store satellite attribute information and orbit data for mission planning. Finally, through the data retrieval experiment, the retrieval time is within 100 milliseconds under ten million pieces of data, which proves that the spatial-temporal grid model has the characteristics of efficient and fast retrieval. It can provide the basic information for satellite mission planning to further improve the efficiency of satellite mission planning and management and the efficiency and quality of satellite mission planning.
Research on Sound velocity model construction method in GNSS-A underwater positioning
Authors: Zhang Jiyong , Sun Xiaohu , Zhao Chunhui , Lei Zhichu , Xie Long , Liu Donghui 
Published: October 2024

Abstract
GNSS-A technology is a submarine positioning technique used to establish ocean control networks, and its positioning results are primarily affected by errors in ocean sound velocity. To address this issue, this paper analyzes the spatial representativeness error of the weighted average sound velocity based on the GNSS-A positioning principle. It also explores the construction method of a sound velocity model in the time domain using the average sound velocity. A sinusoidal diurnal variation model for sound velocity is developed through expanded fitting. Finally, actual measured data is used to perform GNSS-A submarine positioning, verifying the effectiveness of the sound velocity model. The results show that when the horizontal distance of the sound ray is less than 1.7 times the water depth, the average sound velocity does not introduce significant systematic errors. The constructed sound velocity model aligns with local solar elevation patterns, improving the unit weight error of GNSS-A positioning results by several decimeters and controlling the mutual difference of positioning results from different tracks to the decimeter level.
Uncertainty of evaluation of spectral mismatch correction factor
Authors: Rezazadeh Y , Sperling A , Gerloff T , Krüger U , Ferrero A , Campos J , Pellegrino O , Dubard J , Ikonen E 
Published: October 2024

Abstract
Addressing the effect of partially correlated components of spectral irradiance data on spectral integrals poses a substantial challenge. This study employs Monte Carlo methods to conduct an uncertainty analysis of spectral integrals, with a focus on the uncertainty of the spectral mismatch correction factor. The investigation encompasses the primary types of uncertainty contributors of spectral irradiance, based on carefully calibrated FEL lamp measurements. A novel approach is introduced to estimate the impacts of partial correlations among spectral irradiance values at different wavelengths. The findings reveal that uncertainty components arising from partial correlations significantly outweigh those associated with full spectral correlation or complete lack of correlation at different wavelengths. This insight advances our understanding of uncertainty analysis of spectral integrals and underscores the importance of accounting for partial correlations in accurate measurements.
Research on the influence of different organizational structures on the electrical life of sealed relays
Authors: Chen Yangfang , Jin Yangdeng , Ma Siping , Yan Xiaofang , Li Jie , You Yibo , Wan Xinpeng 
Published: October 2024

Abstract
A sealed relay is a type of power relay mainly used in fields with harsh environments, low noise requirements, or high-reliability requirements. It is used in scenarios such as vehicle loads, household appliances, industrial control, and motors. At the same time, when the input meets certain specified conditions, it is a device that can generate a jump in one or more electrical output circuits, playing a role in controlling the on/off current of the connected circuit. Power relays have been widely used in various fields due to their small size, low noise, and low power consumption advantages. This article mainly studies the electrical parameters such as arc energy, arc time, welding force, and contact burning principle of silver tin oxide electrical contact materials produced by different processes, providing a reference for the development of electrical contact materials.
Preparation and properties of new green polyacrylamide hydrogels
Authors: Zhang Lulin , Zhang Taiyang , Qin Lixia , Li Xiangqing , Kang Shizhao 
Published: October 2024

Abstract
The pursuit of low-toxicity hydrogels represents a focal point and frontier in contemporary research endeavors. Partially hydrolyzed polyacrylamide emerges as the most prevalent polymer employed in the formulation of priority flow control gels, owing to its favorable cost-efficiency and heightened receptivity to crosslinking agents. A noteworthy discovery pertains to the utilization of a green crosslinking agent derived from TiSO4, which induces the gelation of polyacrylamide, resulting in an elevation of apparent viscosity from 1159 mPa·s to 100, 000 mPa·s. Extensive investigations into the primary factors influencing the performance of crosslinked polymer gels and their underlying principles have been conducted. The advent of such gel plugging agents holds promise in addressing challenges encountered in select reservoir scenarios, thereby furnishing reliable technical underpinnings for the efficacious stimulation of oil fields.
Preparation of nano-TiO2 spherical catalyst doped with nonmetallic elements for potential use in CO2 reduction
Authors: Yuan Yuan , Ruan Sirui , Ye Yimng , Cai Guojie , Qiu Wenfei , Liu Hongbo , Huang Zhiyong 
Published: October 2024

Abstract
P (St-HEA) microsphere was synthesized as template to prepare TiO2. Nano TiO2 spheres, nitrogen doped TiO2 (N-TiO2) spheres and sulfur doped TiO2 (S-TiO2) spheres were prepared by sol-gel method with the above template. The samples were characterized by XRD, SEM, and XPS. The results showed that TiO2 from sulfur and nitrogen atoms in thiourea and urea in situ doped in the crystal lattice. The TiO2 spherical catalyst doped with nonmetallic elements showed typical anatase phase at lower temperature, and spheres structure with pores and different particle size about 200 nm to 1μm. The obtained TiO2 spherical catalyst doped with nonmetallic elements may potentially use in the photo-catalysis of CO2 reduction.
Diameter controlled fabrication of ultralong silicon wires through regulating metal mass in massive metal-assisted chemical vapor deposition
Authors: Chai Haoyuan , Gu Wenxuan , Xia Xian , Yu Jia , Zhang Bingchang 
Published: October 2024

Abstract
The successful fabrication of ultra-long silicon wires has facilitated the study and application of silicon wires. However, research on the controlled fabrication of ultralong silicon wires, such as diameter modulation, is still insufficient. Herein, tapering ultralong silicon wires are synthesized by using a massive metal-assisted chemical vapor deposition method. By altering the mass of the tin catalyst in the growth zone, the length and changing rate of the diameter can be modulated. When a 40 g catalyst is placed in the growth region, the length of obtained silicon wires is 6.6 mm, and the changing rate of diameter with length is 541 nm/mm. When the catalyst mass in the growth region is reduced to 20 g, the length of the products decreases to 4.0 mm, and the changing rate of diameter with length increases to 964 nm/mm. This work proposes a new route for the diameter-modulated fabrication of ultralong silicon wires and will promote their application across various fields.
Research on friction stir welding technology of urban rail transit car body
Authors: Yan Zhifei , Tang Liguo 
Published: October 2024

Abstract
In this paper, the principle and technical characteristics of friction stir welding are introduced. According to the form of the side wall of urban rail transit vehicles, a friction-stir welding joint structure with convex is proposed. In order to verify the performance of the joint, the joint tensile strength test and the static strength test of the car body are carried out. The results show that the designed friction stir welding joint has high smoothness and excellent performance, fulfilling the requirements for the standard EN12663.
Research on temperature rise performance of DC universal disconnect switch at high altitude
Authors: Wang Yunteng , Zou Hairong , Xiang Honggang , Gong Zuoyong 
Published: October 2024

Abstract
Low Voltage appliances are used more and more widely in high altitude areas, but the research on their temperature rise performance is still insufficient. Aiming at this problem, a high altitude temperature rise simulation model is established and verified by experiment, and the temperature rise performance is studied. Firstly, a DC universal isolation switch with a rated current of 1600A was used as the carrier to build an electro-thermal coupling calculation model of high-altitude temperature rise. Secondly, the temperature rise experiment of the isolation switch in high altitude environment was carried out to verify the effectiveness of the simulation model. Finally, the temperature fields of the DC universal isolation switch at different altitudes are simulated, and the change of convective heat transfer coefficient is calculated, and the temperature rise performance of the isolation switch at high altitudes is analyzed. With the increase of altitude, the temperature rise of the conductor is significantly higher than that of the insulation shell, and the heat dissipation capacity of the aluminum radiator decreases significantly at high altitude. The model and conclusion can provide reference for the use of low voltage electrical apparatus in high altitude environment.
Characteristic of fluoroether gum via non-linear rheological approaches
Authors: Song Ronghao , Yang Rui , Wang Chen , Su Zhengtao 
Published: October 2024

Abstract
Large amplitude oscillatory shear (LAOS) tests were conducted on four types of fluoroether elastomer gum, namely VPL-85540, VPL-75545, VPL-65455, and VPL-55540 in order to study their molecular weight, chain structure, and branching degree from the perspective of rubber rheology. For the setting of shear rate in varied LAOS measurements, frequency and angular velocity controlling modes were attempted and compared. Non-linear rheological parameters showed that VPL-65455 possessed significant polymeric branching characteristics. VPL-55540 possessed the lowest molecular weight, and VPL-75545 was detected with higher long-pendant monomer content in its polymer chain. Rheological properties concluded from the analysis of two shear rate controlling modes of LAOS tests exhibited great consistency, which confirmed the reliability of LAOS tests in the characterization of fluoroether gum.