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Catalyst-Free Defluorosilylation for Synthesis of Silylated gem-Difluoroalkenes and Monofluoroalkenes

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Chinese Journal of Chemistry 2020年第8期38卷 897-898页

作者： long-long Xi State Key Laboratory of Coordination Chemistry Chemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu 210093China

Fluorine containing compounds have an extensive range of application in pharmaceutical and agrochemical fields,in which the C—F bond takes a decisive role.[1]Due to this fact,it is great motivation for chemists to develop expedient synthetic methods for the synthesis of structurally expanded fluorinated ***,cleavage of unactivated C—F bonds is a challenge to make new molecular skeletons.

关键词： compounds bonds skeleton

Multi-Distributed Speech Emotion Recognition Based on Mel Frequency Cepstogram and Parameter Transfer

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Chinese Journal of Electronics 2022年第1期31卷 155-167页

作者： LIN long TAN Liang School of Computer Science Sichuan Normal University Institute of Computing Technology Chinese Academy of Sciences

Speech emotion recognition(SER) is the use of speech signals to estimate the state of emotion. At present, machine learning is one of the main research methods of SER, the test and training data S of traditional machine learning all have the same distribution and feature space, but the data of speech is accessed from different environments and devices, with different distribution characteristics in real life. Thus, the traditional machine learning method is applied to the poor performance of SER. This paper proposes a multi-distributed SER method based on Mel frequency cepstogram(MFCC) and parameter transfer. The method is based on single-layer long short-term memory(LSTM), pre-trained inceptionv3 network and multi-distribution corpus. The speech pre-processed MFCC is taken as the input of single-layer LSTM, and input to the pre-trained inception-v3 *** features are extracted through the pre-trained inception-v3 model. Then the features are sent to the newly defined the fully connected layer and classification layer,let the parameters of the fully connected layer be finetuned, finally get the classification result. The experiment proves that the method can effectively complete the classification of multi-distribution speech emotions and is more effective than the traditional machine learning framework of SER.

关键词： multidistribution corpus fully connected layer feature extraction speech signals machine learning method pre-trained inception-v3 model multidistributed speech emotion recognition pre-trained inception-v3 network feature space recurrent neural nets Mel frequency cepstogram parameter transfer single-layer LSTM speech pre-processed MFCC learning (artificial intelligence) speech recognition emotion recognition multidistributed SER method multidistribution speech emotions

Natural selection contributes to the myopia epidemic

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National Science Review 2021年第6期8卷 128-135页

作者： Erping long Jianzhi Zhang Department of Ecology and Evolutionary Biology University of Michigan State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen University

The prevalence of myopia, or nearsightedness, has skyrocketed in the past few decades, creating a public health crisis that is commonly attributed to lifestyle changes. Here we report an overall increase in the frequencies of myopia-associated mutant alleles over 25 years among participants of the UK *** myopia itself appears to be selected against, many of the mutant alleles are associated with reproductive benefits, suggesting that reproduction-related selection inadvertently contributes to the myopia epidemic. We estimate that, in the UK alone, natural selection adds more than 100 000 myopia cases per generation, and argue that antagonistic pleiotropy be broadly considered in explaining the spreads of apparently disadvantageous phenotypes in humans and beyond.

关键词： allele frequency natural selection antagonistic pleiotropy evolution myopia reproduction

Prediction model for corrosion rate of low-alloy steels under atmospheric conditions using machine learning algorithms

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 337-350页

作者： Jingou Kuang Zhilin long School of Civil Engineering Xiangtan UniversityXiangtan 411105China

This work constructed a machine learning(ML)model to predict the atmospheric corrosion rate of low-alloy steels(LAS).The material properties of LAS,environmental factors,and exposure time were used as the input,while the corrosion rate as the output.6 dif-ferent ML algorithms were used to construct the proposed *** optimization and filtering,the eXtreme gradient boosting(XG-Boost)model exhibited good corrosion rate prediction *** features of material properties were then transformed into atomic and physical features using the proposed property transformation approach,and the dominant descriptors that affected the corrosion rate were filtered using the recursive feature elimination(RFE)as well as XGBoost *** established ML models exhibited better predic-tion performance and generalization ability via property transformation *** addition,the SHapley additive exPlanations(SHAP)method was applied to analyze the relationship between the descriptors and corrosion *** results showed that the property transformation model could effectively help with analyzing the corrosion behavior,thereby significantly improving the generalization ability of corrosion rate prediction models.

关键词： machine learning low-alloy steel atmospheric corrosion prediction corrosion rate feature fusion

Adaptive Takagi-Sugeno fuzzy model and model predictive control of pneumatic artificial muscles

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Science China(Technological Sciences) 2021年第10期64卷 2272-2280页

作者： XIA XiuZe CHENG long School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

Pneumatic artificial muscles(PAMs)usually exhibit strong hysteresis nonlinearity and time-varying features that bring PAMs modeling and control *** characterize the hysteresis relation between PAMs’displacement and fluid pressure,a long short term memory(LSTM)neural network model and an adaptive Takagi-Sugeno(T-S)fuzzy model are *** show that both models perform well under the load free conditions,and the adaptive T-S Fuzzy model can furtherly adapt to the change of load with the online adaptation *** the concise expression and satisfactory performance of the adaptive T-S Fuzzy model,a model predictive controller is designed and *** show that the model predictive controller has a good performance on tracking the given references.

关键词： pneumatic artificial muscles adaptive T-S fuzzy model LSTM neural network model model predictive control

Evolution of the Geological Environment and Exploration for Life on Mars

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Journal of Earth Science 2023年第5期34卷 1626-1628页

作者： long Xiao School of Earth Sciences China University of GeosciencesWuhan 430074China

Nowadays,Mars is a cold desert planet with a nearly vanishing magnetic field,a lack of volcanoes,thin and oxygendepleted atmosphere,and severe solar and cosmic radiation,which is not suitable for the survival and reproduction of ***,Mars is the most similar planetary body to Earth in the solar system:volcanoes(Xiao et al.,2023a;Wilson,2009;Greeley and Spudis,1981),widespread dry vallies and other fluvial landforms(Shi et al.,2022a,b;Zhao et al.,2021;Carr,2006),numerous paleolakes(Michalski et al.,2022;Zhao et al.,2020;Zhao and Xiao,2016);paleo-ocean remnants(Xiao et al.,2023b;Carr and Head,2003;Baker et al.,1991),large-area magnetic anomalies and local residual magnetic fields(Connerney et al.,2005;Stevenson,2001)all indicate that Mars once had intense volcanic activities,thick atmosphere,and an Earth-like warm and humid climate,potentially possessing a habitable environment for carbon-based *** the past billion years,Mars has undergone tremendous changes in the type and intensity of its geological activities and its external environments,making it possible for Mars to serve as a model for Earth's future.

关键词： Earth volcanic fluvial

Quantum Wolf Pack Evolutionary Algorithm of Weight Decision-Making Based on Fuzzy Control

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Chinese Journal of Electronics 2022年第4期31卷 635-646页

作者： LU Na MA long School of Economics and Management Xi’an Aeronautical University

In the traditional quantum wolf pack algorithm, the wolf pack distribution is simplified, and the leader wolf is randomly selected. This leads to the problems that the development and exploration ability of the algorithm is weak and the rate of convergence is ***, a quantum wolf pack evolutionary algorithm of weight decision-making based on fuzzy control is proposed in this paper. First, to realize the diversification of wolf pack distribution and the regular selection of the leader wolf, a dual strategy method and sliding mode cross principle are adopted to optimize the selection of the quantum wolf pack initial position and the candidate leader wolf. Second, a new non-linear convergence factor is adopted to improve the leader wolf’s search direction operator to enhance the local search capability of the algorithm. Meanwhile, a weighted decision-making strategy based on fuzzy control and the quantum evolution computation method is used to update the position of the wolf pack and enhance the optimization ability of the algorithm. Then, a functional analysis method is adopted to prove the convergence of the quantum wolf pack algorithm, thus realizing the feasibility of the algorithm’s global convergence. The performance of the quantum wolf pack algorithm of weighted decision-making based on fuzzy control was verified through six standard test functions. The optimization results are compared with the standard wolf pack algorithm and the quantum wolf pack algorithm. Results show that the improved algorithm had a faster rate of convergence, higher convergence precision,and stronger development and exploration ability.

关键词： Weight factor Fuzzy control Wolf pack evolutionary algorithm Quantum evolution computation

Electromagnetic　Field　Due　to　a　Loop　Antenna　Buried　in　a　Medium　with　Complex　Boundaries

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Journal of Systems Engineering and Electronics 1994年第2期5卷 19-25页

作者： long, yunliang Zhongshan Univ Guangzhou China

The radiation of a loop antenna embedded in a dissipative medium with complex boundaries isanalyzed by a perturbation method and an efficient fast multiple-integration technique. But theperturbation method can not be used directly because there is a finite-length metal cylinder in the vicinityof the loop antenna. The prolate ellipsoid equivalence of the metal cylinder is made, then the cylinder maybe removed and the perturbation method is valid. Numerical results indicate that the approach is accurateat low frequencies and stable.

关键词： Loop antenna Dissipative medium Perturbation method, Good lattice integration.

Design and Control of a Quasi-direct Drive Actuated Knee Exoskeleton

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Journal of Bionic Engineering 2022年第3期19卷 678-687页

作者： yi long yajun Peng Foshan Graduate School of Northeastern University Foshan528000China Faculty of Robot Science and Engineering Northeastern UniversityShenyang110000China Zhongshan Walkbest Intelligent Medical Device Co.Ltd Zhongshan528400China

This paper describes the design and control of a portable and lightweight knee exoskeleton for people with knee *** knee exoskeleton is designed based on our custom quasi-direct drive actuation composed of a DC motor unit and a transmission mechanism encompassing three *** online gait generation method based on gait step calculation and direct measurement using Inertial Measurement Unit(IMU)sensors is proposed to provide continuous assistance during *** on the generated gait trajectory online,Active Disturbance Rejection Control(ADRC)incorporating the feedforward compensation approach is proposed to help the human leg move in consideration of external *** developed knee exoskeleton has been employed successfully to assist impaired users with knee dysfunction to walk in a health recovery *** experimental results indicate that the online gait generation method and the proposed control method are suitable for the knee *** maximum value of the target knee angular position is approximately 50°and the mean of the control torque for the knee joint is located in the interval of[−2 Nm,4 Nm].The developed knee exoskeleton has the potential to regain normal gait to improve strength and endurance during walking in their activities of daily life.

关键词： Exoskeleton Knee dysfunction Quasi-direct drive Active disturbance rejection control Gait generation