Parameter estimation of frequency hopping signal based on time-frequency matrix LCM by Jiamin LIU, Zhijin ZHAO, Junna SHANG, Xueyi YE

“…To improve the performance of the parameter estimation of frequency hopping signal under low signal-to-noise ratio, a parameter estimation algorithm of frequency hopping signal based on time-frequency matrix LCM was proposed.Considering the different characteristics of time-frequency distribution of frequency hopping signal and noise, the mean local energy comparison value of the time-frequency matrix under different scale sliding windows was used, and the multi-scale local energy comparison feature matrix was introduced, so the time-frequency matrix P that only contains the time-frequency information of the frequency hopping signal could be obtained through this feature matrix and the adaptive threshold separation.And then, by extracting the time-frequency hopping information from P, the period, hopping time and frequency of the frequency hopping signal could be accurately estimated.The simulation results show that compared with the traditional local contrast measure (LCM) and morphological filtering method, the proposed algorithm has better frequency hopping signal extraction effect and higher parameter estimation accuracy.And then the tests of the algorithm on the DSP+FPGA hardware system verify the effectiveness and practicability.…”
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齿侧间隙对齿轮副非线性振动特性的影响研究 by 李英明, 陈卫东, 陈奇, 黄康, 邱明明

“…The existence of the backlash can generate impact between teeth,which influences the stability of gear transmission.In order to comprehensive research on the influence of backlash on the gear vibration characteristics,the influences of backlash on the gear pair vibration and impact state under different meshing frequency and different loads are studied,through establishing the mathematical model of gear pair nonlinear vibration,and solving the model numerical simulation based on Runge-Kutta method,combined with time process diagram,phase diagram,Poincaré and FFT frequency spectrogram.The research shows that,the dynamics response of meshing frequency towards backlash is the nonlinear relationship,when the meshing frequency is fixed,within a certain range of backlash,gear chaos appears,out of that range,gear chaos does not appears.When the gear load is lighter,backlash is more likely to influence the vibration characteristics of gear pair,however,when the load is heavy,the influence is smaller.With the increase of backlash,the gear impact state transits from bilateral impact to unilateral impact.when it surpass the threshold,the impact of unilateral state will be maintained and unchanged.…”
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Evolutionary Artificial Intelligence Algorithm for Optimizing Step Phase Detection Based on Foot-Mounted Triaxial Accelerometer Data by P. A. Khmarskiy

“…Experiments involving walking along a closed square path confirmed the high accuracy and robustness of the proposed method: the match between the optimized and reference trajectories demonstrates the practical applicability of the approach for precise gait reconstruction under different conditions. …”
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A fair and efficient two-step procedure for sugarcane properties prediction based on near-infrared spectra by Luiz Alexandre Peternelli, Andréa Carla Bastos Andrade, Cristina Silva Dias, Reinaldo Francisco Teófilo

“…In the initial phase of a breeding program, researchers might focus on classifying individuals as selected or not based on whether they display a property value above or below a specific threshold. Integrating classification methods with near-infrared (NIR) spectroscopy is essential for effective selection. …”
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An Integrated Fault Identification Approach for Rolling Bearings Based on Dual-Tree Complex Wavelet Packet Transform and Generalized Composite Multiscale Amplitude-Aware Permutatio... by Wuqiang Liu, Xiaoqiang Yang, Shen Jinxing

“…Besides, this solution can judge the different faults more accurately compared with other ordinary methods.…”
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Suitability of Utilization of Compositional Nutrient Diagnosis on Diagnosis of Foliar Nutrient in Litchi and Longan by Yongcong ZHU, Donglin LUO, Cuihua BAI, Lixian YAO

“…The problems of compositional nutrient diagnosis (CND) approach in determining the high-yield levels of litchi and longan were examined, with the aim to identify whether CND is a suitable approach for diagnosis of foliar nutrient in litchi and longan.【Method】A total of 511 leaf samples of litchi (Litchi chinensis Sonn) (c.v. …”
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Estimation of Phenology Stages of Rapeseed Using Remote Sensing Vegetation Indices and Digital Camera Images Index by Akbar Mirahmadi, Hojjatollah Yazdan Panah, Mehdi Momeni

“…According to Pearsonchr('39')s correlation test, GCC index data are correlated with NDVI and Brightness index data .we used the ratio threshold, rate of change and first derivative methods, to estimate "start of season" and "end of season" and the results showed that the first derivative and ratio threshold methods with an average difference of 18 and 19 days in the "start of the season"  and the rate of change method, with an average difference of 8 days, has the best performance in estimating the “end of the season”. …”
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Consistency control of grid-connected substation voltage regulation based on photovoltaic inverter power coordination by Jun Liu, Fan Yang, Bingbing Lu, Lijia Ren

“…The experimental results show that this method can effectively reduce the voltage fluctuations caused by the distributed photovoltaic access, control the maximum instantaneous overvoltage of transformers within the set threshold range, improve the accuracy of voltage regulation consistency control in the grid-connected substations, and ensure the stable operation of the power grid.…”
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Post-integration based point-line feature visual SLAM in low-texture environments by Yanli Liu, Zhengyuan Feng, Heng Zhang, Wang Dong

“…Abstract To address the issues of weak robustness and low accuracy of traditional SLAM data processing algorithms in weak texture environments such as low light and low contrast, this paper first studies and improves the data feature extraction method, optimizing the AGAST-based feature extraction algorithm to adaptively adjust the extraction threshold according to the gradient size of different data features. …”
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Attention activation network for bearing fault diagnosis under various noise environments by Yu Zhang, Lianlei Lin, Junkai Wang, Wei Zhang, Sheng Gao, Zongwei Zhang

“…However, bearings often operate in noisy environments, especially during failures, which poses a challenge to most current deep learning methods that assume noise-free data. Therefore, this paper designs a Multi-Location Multi-Scale Multi-Level Information Attention Activation Network (MLSCA-CW) with excellent performance in different kinds of strong noise environments by combining soft threshold, self-activation, and self-attention mechanisms. …”
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Impact of Forms of Visual Attenuation on Short-Term Eye Changes Under Controlled Reading Visibility by Su H, Chun RKM, De Lestrange-Anginieur E

“…Additional defocusing failed to exacerbate axial elongation under sub-threshold text visibility (mean difference: − 0.135 μm ± 2.783 μm), revealing a clear inhibitory effect of lowering visibility on eye changes. …”
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Two-phase linear relationship of Vitamin D and Vitamin A among children aged 0–14 years: a cross-sectional study by Wenyuan Liu, Qiao Wang, Bibo Mao, Fei Xu, Yefang Ke, Shengying Zhang, Chenbo Zhou, Chunyan Liu, Wenbo Lu, Jishan Zheng

“…BackgroundVitamin D and Vitamin A are crucial for children’s immune function, bone health, and cellular growth, but their interrelationship and the impact of various factors remain poorly understood.ObjectiveTo explore the relationship between Vitamin D and Vitamin A levels in children and identify any critical thresholds.MethodsA cross-sectional study was conducted from 2018 to 2021 in Ningbo, Zhejiang, China. …”
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Influence of Gaussian noise and Levy noise on the phase dynamics of the ensemble of Kuramoto-like oscillators of first and second order by Arinushkin, Pavel Alekseevich, Kupriyanov, Vladislav Dmitrievich, Vadivasova, Tatjana Evgenevna

“…  Methods. In this paper, two ensembles of Kuramoto-like phase oscillators with the same topology but different number of oscillators are investigated. …”
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WPD-Based Noise Reduction for Microseismic Data Through Adaptive Coefficient Shrinkage and Multi-Basis Fusion by Yaqi Zhang, Zhiqiang Lan, Zheng Shi, Yuhang Xue, Jie Wang, Kun Zhu, Jian He, Xiujian Chou

“…Firstly, this method utilizes energy filtering to eliminate noise that is not temporally correlated with microseismic waveforms, then employs time-varying thresholds to refine the edges of these waveforms, effectively leveraging time and amplitude information to preserve the details of waveform edge. …”
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W ciemnościach tunelu, 
czyli o zjawisku leksykalnego plateau by Anna Seretny

“…It is necessary to choose different methods of teaching/learning at B2 level, otherwise the progress in learning can be slowed (the language learning plateau). …”
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Optimization of the Driving Mode Transformation of Hybrid Electric Bus based on Genetic Algorithm by Zhao Lijun, Li Shoucheng, Wei Guangpu, Zhang Hongsheng

“…The hybrid electrical city bus has two power sources to drive vehicle,so the control of vehicle driving mode transformation is become the core of the vehicle control strategy.It not only influences the vehicle fuel economy and emissions,but also influences the driving comfort of the vehicle.An HEV simulation model is built for performance analysis by interlinking of advanced software AVL CRUISE and Matlab/Simulink.By adjusting threshold of the driving mode transformation,the mode can be transformed smoothly.For achieving minimum equivalent fuel consumption,the genetic algorithm（GA）optimization method is applied to get the optima of control parameters which affect the vehicle driving mode transformation in different city bus cycles including Europe and China.The vehicle fuel economy is further improved.…”
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Chinese Word Identification and Sentence Intelligibility in Primary School Classrooms by Jianxin PENG, Peng JIANG

“…A method based on the sentence test is more useful for speech intelligibility evaluation in classrooms than that based on the word test for different age groups. …”
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试验场载荷特征分析与标准化方法研究 by 施闯闯, 赵礼辉, 顾振飞, 叶沛, 翁硕, 郑松林

“…In view of the problem that the collection of vehicle load must be completed after the prototype car is completed,and the necessary load data are often lacking in the product development stage,the standardization of load spectrum under the endurance criterion of the proving ground is studied in this paper.Firstly,the characteristics of the measured load spectrum of different vehicle types in a domestic proving ground are analyzed,and the consistency of the frequency distribution of rainflow cycles for different vehicle types is clarified.Furthermore,the validity of the traditional probability distribution model and the extreme value distribution model in the rainflow cycle modeling is compared by synthesizing the difference of load frequency distribution and damage interval distribution.Through load frequency and damage distribution,the rationality of the exceeding threshold distribution model in load modeling is verified.Finally,the standardized load model of the proving ground is established by normalizing the loads of different types of vehicles.The validity and rationality of the standardized load model are verified by comparing the rainflow cycle,pseudo-damage and fatigue life of the standardized load spectrum with the measured load spectrum in proving grounds.The standardized load spectrum and load spectrum standardization method can provide accurate and effective load data for new vehicle in the early development stage,so as to ensure product reliability and durability level.…”
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Association between pan-immune-inflammation value and heart failure: Evidence from the NHANES 2011–2020 by Chen Fu, Yijie Mao

“…Furthermore, we identified an inflection point of logarithmic pan-immune-inflammation value = 5.98 as a critical threshold. Stratified analyses revealed that the association between pan-immune-inflammation value and heart failure occurrence remains consistent across different subgroups. …”
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An increase in visceral fat is associated with a decrease in the taste and olfactory capacity. by Jose Carlos Fernandez-Garcia, Juan Alcaide, Concepcion Santiago-Fernandez, M M Roca-Rodriguez, Zaida Aguera, Rosa Baños, Cristina Botella, Rafael de la Torre, Jose M Fernandez-Real, Gema Fruhbeck, Javier Gomez-Ambrosi, Susana Jimenez-Murcia, Jose M Menchon, Felipe F Casanueva, Fernando Fernandez-Aranda, Francisco J Tinahones, Lourdes Garrido-Sanchez

“…<h4>Materials and methods</h4>179 females with different weights (from low weight to morbid obesity) were studied. …”
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