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Quantification of Central and Eastern China's atmospheric CH_(4) enhancement changes and its contributions based on machine learning approach

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Journal of Environmental Sciences 2024年第4期138卷 236-248页

作者： Xinyue Ai Cheng Hu Yanrong Yang Leying Zhang Huili Liu Junqing Zhang Xin Chen Guoqiang Bai Wei Xiao college of Biology and the Environment Joint Center for sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjing 210037China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China guang’an vocational&technical college Guangan 638550China HuaNan Meteorological Administration Huanan 154400China

Methane is the second largest anthropogenic greenhouse gas,and changes in atmospheric methane concentrations can reflect the dynamic balance between its emissions and ***,the monitoring of CH_(4) concentration changes and the assessment of underlying driving factors can provide scientific basis for the government’s policy making and *** is the world’s largest emitter of anthropogenic ***,due to the lack of ground-based observation sites,little work has been done on the spatial-temporal variations for the past decades and influencing factors in China,especially for areas with high anthropogenic emissions as Central and Eastern *** to quantify atmospheric CH_(4) enhancements trends and its driving factors in Central and Eastern China,we combined the most up-to-date TROPOMI satellite-based column CH_(4)(xCH_(4))concentration from 2018 to 2022,anthropogenic and natural emissions,and a random forest-based machine learning approach,to simulate atmospheric xCH_(4) enhancements from 2001 to *** results showed that(1)the random forest model was able to accurately establish the relationship between emission sources and xCH_(4) enhancement with a correlation coefficient(R^(2))of 0.89 and a root mean-square error(RMSE)of 11.98 ppb;(2)The xCH_(4) enhancement only increased from 48.21±2.02 ppb to 49.79±1.87 ppb from the year of 2001 to 2018,with a relative change of 3.27%±0.13%;(3)The simulation results showed that the energy activities and waste treatment were the main contributors to the increase in xCH_(4) enhancement,contributing 68.00% and 31.21%,respectively,and the decrease of animal ruminants contributed-6.70% of its enhancement trend.

关键词： TROPOMI Methane column concentrations Anthropogenic sources Random Forest model

Optimization design and experiment of the variable differential gear train planting mechanism

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 85-93页

作者： Xiong Zhao Ziwei Liu Yuanwu Jia Xingxiao Ma Pengfei Zhang Jianneng Chen School of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Xi’an International University Engineering college Xi’an 710077China Hangzhou vocational&technical college Hangzhou 310018China

In order to improve the adaptability of the planting mechanism for different plant spacings,a variable differential gear train planting mechanism based on precise pose and trajectory control was proposed by combining the open chain 2R rod group and the variable differential gear *** to the pose requirements of receiving seedling point,transporting seedling point and planting point,three precise pose points of constrained planting trajectory were *** the three-position motion generation structural synthesis method,combined with computer-aided optimization design software,a set of mechanism parameters that meet the planting requirements were *** on the optimized mechanism parameters,by only changing the coordinates of two trajectory shape control points,three planting trajectories with key point position information adapted to 300 mm,400 mm and 500 mm plant spacing were obtained by interpolation,and three pairs of total transmission ratio of three groups of variable differential gear trains were *** distributing the total transmission ratio of the mechanism,the fixed axis gear train and the differential gear train are *** fixed axis gear train included a pair of non-circular gear pairs and a pair of positive gear pairs,which were convenient for disassembly and *** former drives the sun gear at variable speed,and the latter drives the planet carrier at uniform *** on this structure,the transmission ratio of the positive gear pair is-1,and the transmission ratio of the differential gear train is *** sub-transmission ratio of the single-stage non-circular gear pair was calculated and the pitch curves of three pairs of noncircular gears were *** pairs of non-circular gear pairs with different transmission ratios were replaced in turn and three sets of planting mechanisms were modeled in three *** virtual prototype motion simulation was completed by ADAMS software,and the p

关键词： plant spacing planting mechanism variable differential gear train precise pose trajectory control parameter optimization

Design and experimental study of the end-effector for broccoli harvesting

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 137-144页

作者： Xiong Zhao Gangji Xu Pengfei Zhang Gaohong Yu Yadan Xu Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Transplanting Equipment and Technology of Zhejiang Province Hangzhou 310018China Hangzhou vocational&technical college Hangzhou 310018China

The end-effector is an important part of the broccoli harvesting *** at the physical characteristics of a large broccoli head and thick stem,a spherical cutting tool broccoli harvesting end-effector was designed in this ***,the physical characteristics of broccoli were tested,and physical parameters such as the broccoli head diameter and stem diameter of broccoli were *** maximum cutting force of broccoli stems under different cutting angles was ***,according to the physical characteristics and harvesting process of broccoli,the end-effector was designed,and the mathematical model of kinematics and dynamics was *** on the results of dynamic analysis,the end-effector rod was optimized,and the unilateral width of the slider was 40 mm,the length of the connecting rod was 120 mm,and the length of the crank was 42 *** mechanism needed an external driving force of 140.54 N to cut the broccoli ***,a 32 mm cylinder with a load rate of 50%was selected as the power ***,the feasibility of the broccoli harvesting end-effector was verified by the harvesting *** showed that the overall harvesting success rate of the end-effector is 93.3%,and the smoothness rate of the stem section is 83.3%.The harvesting performance of the broccoli end-effector was *** lays a foundation for agricultural robots to harvest broccoli.

关键词： harvesting robot broccoli end-effector dynamic analysis mechanism optimization

An epidermal electrode based triboelectric walking energy harvester for wearable wireless sensing applications

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Science China(Technological Sciences) 2024年第3期67卷 949-957页

作者： CHANG ShiYuan LIU FuHai CHEN JinKai XIA LianBin ZHOU Hao JIANG JingYang DONG Kang ZHANG ChenHao WU Yun CHEN Jin XUAN Weipeng SUN LingLing JIN Hao DONG ShuRong LUO JiKui Ministry of Education Key Laboratory of RF Circuits and Systems Hangzhou Dianzi UniversityHangzhou 310018China Special Equipment college Hangzhou Vocational&Technical CollegeHangzhou 310018China college of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 330027China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China

Harvesting bio-kinetic energy using a triboelectric nanogenerator(TENG) is one of the promising routes to solve the sustainable energy supply problem for wearable electronics. However, additional materials, complex fabricating processes or specific mechanical structures are needed for existing TENGs to harvest bio-kinetic energy. Besides, they need to be tightly attached to the human body, which may result in detachment and malfunction under tense human motion. Herein, an intrinsic epidermal electrode-based TENG(E-TENG) is proposed to harvest human walking energy. The wearing shoes and ground are used as tribo-materials, and the human epidermis is used as the back electrode of the E-TENG. Compared with the traditional TENGs,the E-TENG does not need any additional tribo-materials and complex mechanical structures. Under optimal conditions, the voltage output of E-TENG can reach 914 V. E-TENG has been used as a self-powered warning sensor and pedometer sensor for demonstration. Furthermore, E-TENG based self-powered wireless sensor system has been developed using a newly designed micro energy electronic switch(MEES). Ambient ultraviolet intensity, temperature and humidity information can be monitored and then transmitted to mobile phone every 3.5 min, demonstrating great potential for widespread wearable applications.

关键词： triboelectric nanogenerator wearable wireless sensing self-powered

A survey on semantic communications:Technologies,solutions,applications and challenges

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Digital Communications and Networks 2024年第3期10卷 528-545页

作者： Yating Liu Xiaojie Wang Zhaolong Ning MengChu Zhou Lei Guo Behrouz Jedari School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Baotou vocational&technical college Baotou 014035China School of Information and Electronic Engineering Zhejiang Gongshang UniversityHangzhou 310018China Department of Electrical and Computer Engineering New Jersey Institute of TechnologyNewarkNJ 07102USA Nokia Finland

Semantic Communication(SC)has emerged as a novel communication paradigm that provides a receiver with meaningful information extracted from the source to maximize information transmission throughput in wireless networks,beyond the theoretical capacity *** the extensive research on SC,there is a lack of comprehensive survey on technologies,solutions,applications,and challenges for *** this article,the development of SC is first reviewed and its characteristics,architecture,and advantages are ***,key technologies such as semantic extraction,semantic encoding,and semantic segmentation are discussed and their corresponding solutions in terms of efficiency,robustness,adaptability,and reliability are *** of SC to UAV communication,remote image sensing and fusion,intelligent transportation,and healthcare are also presented and their strategies are ***,some challenges and future research directions are presented to provide guidance for further research of SC.

关键词： Semantic communication Semantic coding Semantic extraction Semantic communication framework Semantic communication applications

Impact of Exercise Atmosphere on Adolescents’Exercise Behavior:Chain Mediating Effect of Exercise Identity and Exercise Habit

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International Journal of Mental Health Promotion 2024年第7期26卷 579-588页

作者： Zhen Su Ziqiang Zhang Yonghao Zhou Physical Education and Military Training Department Zhijiang College of Zhejiang University of TechnologyHangzhou312000China Basic Department Zhejiang Changzheng Vocational&Technical CollegeHangzhou310023China Physical Education Department Hangzhou Medical CollegeHangzhou310059China

Appropriate physical exercise has a positive impact on adolescents’physical and mental health,but there is a serious lack of physical exercise among Chinese *** to shape their exercise behavior(EB)has become an important task in promoting their development.A questionnaire survey was conducted using stratiﬁed cluster random sampling on three middle schools by class in Zhejiang Province,China to investigate the impact of exercise atmosphere(EA)on adolescents’exercise behavior and the mediating role of exercise identity(EI)and exercise habit(EH).806 adolescents were investigated by the Exercise Atmosphere Scale(EAS),Exercise-Identity Scale(EIS),Self-Report Habit Index(SRHI),and Physical Activity Rating Scale(PARS-3).The results show that:There is a signiﬁcant positive correlation between each two of exercise atmosphere,exercise identity,exercise habit,and exercise behavior(p<0.05).Exercise atmosphere could not only directly affect adolescents’physical exercise behavior but can also indirectly affect their physical exercise behavior through the mediating effect of exercise identity and exercise habit,involving three mediating pathways,namely,the mediating path through exercise identity,the mediating pathway through exercise habit and the chain mediating pathway through exercise identity and exercise *** direct effect of exercise atmosphere on exercise behavior was 0.459(p<0.01),accounting for 62.62% of the total effect of 0.733,and its indirect effect was 0.274,accounting for 37.28% of the total *** a certain extent,the mediating effect model reveals the mechanism of exercise atmosphere affecting exercise behavior and has a certain reference value for promoting adolescents’exercise *** should start by creating an exercise atmosphere,cultivating exercise identity,and enhancing exercise habits to help teenagers form active physical exercise behaviors.

关键词： Exercise atmosphere exercise identity exercise habit exercise behavior

Analyze the Performance of Electroactive Anticorrosion Coating of Medical Magnesium Alloy Using Deep Learning

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Computers, Materials & Continua 2024年第4期79卷 263-278页

作者： Yashan Feng Yafang Tian Yongxin Yang Yufang Zhang Haiwei Guo Jing’an Li Advanced Functional Materials Laboratory Zhengzhou Railway Vocational and Technical CollegeZhengzhou450000China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450000China

Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion protection.A first-time proposal, the total acidity (TA) potential of the hydrogen (pH) concept significantly shapes medicalmagnesium alloys. These coatings are meticulously designed for robust corrosion resistance, blending theoreticalinsights and practical applications to enhance our grasp of corrosion prevention mechanisms and establisha systematic approach to coating design. The groundbreaking significance of this study lies in its innovativeintegration of the TA/pH concept,which encompasses the TA/pH ratio of the chemical environment. This approachsurpasses convention by acknowledging the intricate interplay between the acidity and pH levels within thecoating formulation, thereby optimizing metal-phosphate-based conversion coatings and transforming corrosionmitigation strategies. To authenticate the TA/pH concept, the study comprehensively compares its findings withexisting research, rigorously validating the theoretical framework and reinforcing the correlates among TA/pHvalues and observed corrosion resistance in the coatings. The influence of mutations that occur naturally inthe detergent solution on persistent phosphorus changes is shown by empirical confirmation, which improvescorrosion resistance. This realization advances the field ofmaterials and the field’s knowledge of coated generation,particularly anticorrosion converter layers.

关键词： Medical magnesium alloys hydrogen gas anticorrosion total acidity potential of the hydrogen(pH)

Cost-Based Research on Energy Management Strategy of Electric Vehicles Using Hybird Energy Storage System

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Tsinghua Science and Technology 2024年第3期29卷 684-697页

作者： Juanying Zhou Jianyou Zhao Lufeng Wang School of Automobile Chang’an UniversityXi’an 710064Chinaand also with College of Automotive Engineering and General AviationShaanxi Vocational and Technical CollegeXi’an 710038China School of Automobile Chang’an UniversityXi’an 710064China college of Automobile Shaanxi College of Communication TechnologyXi’an 710018China

This paper uses the minimization and weighted sum of battery capacity loss and energy consumption under driving cycles as objective functions to improve the economy of Electric Vehicles(EVs)with an hybrid energy storage system composed of power batteries and ***,Dynamic Programming(DP)is employed to determine the objective function values under different weight coefficients,the comprehensive cost consisting of battery aging and power consumption costs,and the relationship between the hybrid power *** also evaluate the real-time fuzzy Energy Management Strategy(EMS),fuzzy control strategies,and a strategy based on DP using the World Light vehicle Test Procedure(WLTP)driving cycle and a synthesis driving cycle derived from New European Driving Cycle(NEDC),WLTP,and Urban Dynamometer Driving Schedule(UDDS)as ***,the proposed strategy is compared with the fuzzy control strategy and the strategy based on *** with fuzzy energy management strategy(namely FZY-EMS),the proposed EMS reduces the battery capacity loss and system energy *** results demonstrate the effectiveness of the proposed EMS in improving EV economy.

关键词： automobile engineering hybrid energy storage Energy Management Strategy(EMS) fuzzy control strategy

Genome wide association analysis identifies candidate genes for fruit quality and yield in Actinidia eriantha

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Journal of Integrative Agriculture 2024年第6期23卷 1929-1939页

作者： Yingzhen Wang Ying Wu Xinlei Wang Wangmei Ren Qinyao Chen Sijia Zhang Feng Zhang Yunzhi Lin Junyang Yue Yongsheng Liu School of Horticulture Anhui Agricultural UniversityHefei 230036China School of Forestry Science and Technology Lishui Vocational and Technical CollegeLishui 323000China college of Life Science Sichuan UniversityChengdu 610064China

Quality and yield are the primary concerns in kiwifruit breeding,but research on the genetic mechanisms of fruit size,shape,and ascorbic acid(ASA)content is currently very limited,which restricts the development of kiwifruit molecular *** this study,we obtained a total of 8.88 million highly reliable single nucleotide polymorphism(SNP)markers from 140 individuals from the natural hybrid offspring of Actinidia eriantha cv.‘White’using whole genome resequencing technology.A genome-wide association study was conducted on eight key agronomic traits,including single fruit weight,fruit shape,ASA content,and the number of inflorescences per branch.A total of 59 genetic loci containing potential functional genes were located,and candidate genes related to single fruit weight,fruit length,ASA content,number of inflorescences per branch and other traits were identified within the candidate interval,such as AeWUSCHEL,AeCDK1(cell cycle dependent kinase),AeAO1(ascorbic oxidase)and AeCO1(CONSTANS-like 4).After constructing an RNAi vector for AeAO1 and injecting it into the fruit of cv.‘Midao 31’to interfere with the expression of the AeAO1 gene,the results showed that the activity of ascorbic oxidase in the fruit of‘Midao 31’significantly decreased,while the content of ASA significantly *** study provides valuable insights into the genetic basis of variation in *** fruit traits,which may benefit molecular marker-assisted breeding efforts.

关键词： Actinidia eriantha GWAS SNP QTLs fruit quality