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Response of maize growth and soil biological characteristics to planting density under fertigation in a semi-arid region

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International Journal of agricultural and Biological engineering 2024年第2期17卷 186-192页

作者： Peng Jiang Lei Li Dejia Xu Rui Wang Quan Sun school of forestry and Prataculture Ningxia UniversityYinchuan 750021China Institute of agricultural Resources and Environment Ningxia Academy of Agriculture and Forestry SciencesYinchuan 750002China school of Agriculture Ningxia UniversityYinchuan 750021China

Increasing the planting density can exacerbate crop competition for water,nutrients and space which results in a decline in the crop ***,the effect of increasing planting density on crop growth and soil biological characteristics in barren sandy land in the semi-arid regions are still *** this study,we investigated the effects of six planting densities(5.4×10^(4),6.45×10^(4),7.95×10^(4),9.5×10^(4),9.75×10^(4) and 10.5×10^(4) plants/hm^(2))on maize growth,photosynthesis characteristics,yield and soil biological characteristics in barren sandy soil in the semi-arid region of Ningxia,*** results indicated that the stem diameter and spike length decreased linearly with increasing planting *** plant height,spike weight,grain weight and 100-grain weight decreased with increasing plating ***,the root length increased with increasing planting *** diameter,volume and activity increased and then decreased with increasing planting *** was no significant difference(p>0.05)in the effect of planting density on transpiration rate intercellular CO_(2) *** well,the soil microbial biomass carbon and microbial biomass nitrogen decreased with increasing planting *** soil catalase activities increased and then decreased with increasing planting *** alkaline phosphatase activity,the amounts of soil bacteria and actinomycetes increased with increasing planting ***,a moderately increasing planting density can improve maize yield when water and nutrients are *** optimal planting density was 8.29×10^(4) plants/hm^(2) and the highest yield was 15.84 t/hm^(2) in barren sandy soil in semi-arid region of Ningxia,*** study provides a theoretical basis for high yield and high efficiency of maize.

关键词： maize growth planting density yield fertigation soil enzyme activity

Method for the navigation line recognition of the ridge without crops via machine vision

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International Journal of agricultural and Biological engineering 2024年第2期17卷 230-239页

作者： Wei Liu Jianping Hu Jiaxin Liu Rencai Yue Tengfei Zhang Mengjiao Yao Jing Li school of agricultural engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Some agriculture machinery like the transplanter,needs to operate by following the crop-free *** order to improve working efficiency and quality,some autonomous navigation systems were developed and applied to ridge-following *** present,agricultural navigation systems are mainly the satellite navigation system and the machine vision *** satellite navigation system is difficult to apply to the machinery that needs to work by following the ridge because it cannot distinguish the shape of the navigated ridge and guide the machinery working along the *** this study,697 cloudy ridge images and 235 sunny ridge images were taken in the field,and these images were used as the ***,a machine vision navigation method based on the color of ridges was ***,the regions of interest(ROI)in the ridge image were extracted according to the reaction time and the forward speed of the ***,a gray reconstruction method was used to enlarge the color difference between the ridge and the *** optimal threshold for the gray image segmenting was calculated real-timely by using the threshold segmentation ***,based on the contour detection method,the ridge contour which was not surrounded by holes was ***,the approximate quadrilateral method was proposed to recognize the ridge center line as the navigation *** method proposed in this study was verified by four types of ridges with different colors and *** experimental results showed that the recognition success rates of the light ridge,the dark ridge,the film-covered ridge,and the sunny ridge were 100%,97.5%,100%,and 98.7%,*** recognition success rate of the proposed method was at least 8%higher than that of the existing ridge-furrow recognition *** results indicate that this method can effectively realize navigation line *** method can provide technical support for the autonomous navigation of agricultural mac

关键词： navigation line recognition machine vision ridge line recognition intelligent agriculture

A calibration and compensation method for an industrial robot with high accuracy harmonic reducers

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Science China(Technological Sciences) 2024年第3期67卷 725-739页

作者： ZHAO YiYang LIU Xun CAO JiaBin LIU JinYu XU Yan YAN WeiXin school of Mechanical engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Computer and Control engineering Northeast Forestry UniversityHarbin 150040China

Industrial serial robots need high stiffness to keep absolute pose accuracy and meet the requirements in practical applications. However, the weak stiffness feature of robot joints and the payloads affected on robot end-effector, which will also increase the pose error of robot. Especially, the existing calibration methods often consider under no-payload condition without discussing the payload state. In this paper, we report a new industrial serial robot composed by a new harmonic reducer: Model-Y, based on high accuracy and high stiffness, and a kinematic parameter calibration algorithm which is based on a harmonic reducer forcedeformation model. To decrease the accuracy effects of payload, an iterative calibration method for kinematic parameters with payload situation was proposed. Simulation and experiments are conducted to verify the effectiveness of the proposed calibration method using the self-developed industrial serial robot. The results show a remarkably improved accuracy in absolute position and orientation with the robot's payload range. The position mean error has 70% decreased to 0.1 mm and the orientation mean error diminished to less than 0.01° after calibration with compensation. Additionally, online linear and circular tests are carried out to evaluate the position error of the robot during large-scale spatial and low-speed continuous movement. The accuracy is consistent with the previous calibration results, indicating the effectiveness and advantages of the proposed strategy in this article.

关键词： industrial serial robot Model-Y harmonic calibration stiffness model online compensation

Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor

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engineering 2024年第6期37卷 230-245页

作者： Chang-Kai Wen Wen Ren Qing-Zhen Zhu Chun-Jiang Zhao Zhen-Hao Luo Sheng-Li Zhang Bin Xie Zhi-Jun Meng Research Center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Intelligent agricultural Power Equipment Beijing 100097China BYD Company Limited Shenzhen 518118China College of agricultural engineering Jiangsu UniversityZhenjiang 212013China College of engineering China Agricultural UniversityBeijing 100083China

In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension *** paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a ***,the tractor is prototyped and assembled,and ploughing tests are carried *** ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution *** with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy *** study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions.

关键词： Electric tractor Ploughing unit Torque distribution Active ballast Traction performance

High-Value-Added Utilization of Turpentine:Screening of Anti-Influenza Virus Agents fromβ-Pinene Derivatives

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Journal of Renewable Materials 2024年第1期12卷 45-56页

作者： Yiwen Li Hongyan Si Peng Wang Hai Luo Minggui Shen Xiaoping Rao Zhanqian Song Shibin Shang Zongde Wang Shengliang Liao East China Woody Fragrance and Flavor engineering Research Center of National forestry and Grassland Administration Camphor Engineering Research Center of National Forestry and Grassland AdministrationCollege of ForestryJiangxi Agricultural UniversityNanchang330045China Institute of Chemical Industry of forestry Products China Academy of ForestryNational Engineering Laboratory for Biomass Chemical UtilizationKey and Open Laboratory of Forest Chemical EngineeringState Forestry AdministrationKey Laboratory of Biomass Energy and MaterialJiangsu ProvinceNanjing210042China College of Chemical engineering Huaqiao UniversityXiamen361021China

Turpentine is a renewable and resourceful forest *** deep processing and utilization of turpentine,particularly its primary componentβ-pinene,has garnered widespread *** study aimed to synthesize 40 derivatives ofβ-pinene,including nopinone,3-cyanopyridines of nopinone,myrtanyl acid,myrtanyl acylthioureas,and myrtanyl *** assessed the antiviral activities of theseβ-pinene derivatives against influenza virus A/Puerto Rico/8/34(H1N1)using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide ***β-pinene derivatives were used before and after cellular infection with the influenza virus to evaluate their preventive and therapeutic effects against the H1N1 *** results showed that only compound 10o exhibited a preventive effect against the H1N1 virus with a half-maximal inhibitory concentration(IC50)value of 47.6μmol/*** the compounds,4e,4i,and 4l demonstrated therapeutic effects against cellular infection,with compound 4e displaying the most potent therapeutic effect(IC50=17.5μmol/L),comparable to the positive control *** findings indicated that certainβ-pinene derivatives exhibited in vitro antiviral activity against the H1N1 influenza A virus,warranting further investigation as potential anti-influenza agents.

关键词： Antiviral activity β-pinene derivative 3-cyanopyridine influenza virus

KnowledgeMapping of Hybrid Solar PV andWind Energy Standalone Systems: A Bibliometric Analysis

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Energy engineering 2024年第7期121卷 1781-1803页

作者： Quan Zhou Haiyang Li school of Mechanical and Electrical engineering Central South University of Forestry and TechnologyChangsha410004China

Renewable energy is becoming more attractive as traditional fossil fuels are rapidly depleted and expensive,and their use would release *** systems that use both wind and solar energy are more reliable and efficient than those that utilize only one *** renewable energy systems(HRES)are viable for remote areas operating in standalone *** paper aims to present the state-of-the-art research on off-grid solar-wind hybrid energy systems over the last two *** than 1500 published articles extracted from the Web of Science are analyzed by bibliometric methods and processed by CiteSpace to present the results with figures and *** countries and highly cited authors are identified,and hot topics with hotspot articles are shown in landscape and timeline *** trends and new developments related to techno-economic analysis and microgrids,as well as the application of HOMER software,are predicted based on the analysis of citation ***,the opportunities of hybrid energy systems for sustainable development are discussed,and challenges and possible solutions are *** study of this paper provides researchers with a comprehensive understanding and intuitive representation of standalone solar-wind hybrid energy systems.

关键词： Wind energy solar PV standalone citation bursts emerging trends

Multi-modal knowledge graph inference via media convergence and logic rule

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 211-221页

作者： Feng Lin Dongmei Li Wenbin Zhang Dongsheng Shi Yuanzhou Jiao Qianzhong Chen Yiying Lin Wentao Zhu school of Information Science and Technology Beijing Forestry UniversityBeijingChina engineering Research Center for forestry-oriented Intelligent Information Processing National Forestry and Grassland AdministrationBeijingChina Michigan Technological University HoughtonMichiganUSA

Media convergence works by processing information from different modalities and applying them to different *** is difficult for the conventional knowledge graph to utilise multi-media features because the introduction of a large amount of information from other modalities reduces the effectiveness of representation learning and makes knowledge graph inference less *** address the issue,an inference method based on Media Convergence and Rule-guided Joint Inference model(MCRJI)has been *** authors not only converge multi-media features of entities but also introduce logic rules to improve the accuracy and interpretability of link ***,a multi-headed self-attention approach is used to obtain the attention of different media features of entities during semantic ***,logic rules of different lengths are mined from knowledge graph to learn new entity ***,knowledge graph inference is performed based on representing entities that converge multi-media *** experimental results show that MCRJI outperforms other advanced baselines in using multi-media features and knowledge graph inference,demonstrating that MCRJI provides an excellent approach for knowledge graph inference with converged multi-media features.

关键词： logic rule media convergence multi-modal knowledge graph inference representation learning

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： He-xiang Wu Jia Qu Lin-zhi Wu Key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China school of Civil engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

Reshaping Li–Mg hybrid batteries:Epitaxial electrodeposition and spatial confinement on MgMOF substrates via the lattice‐matching strategy

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Carbon Energy 2024年第8期6卷 248-261页

作者： Yongqin Wang Fulin Cheng Jiawen Ji Chenyang Cai Yu Fu school of Materials Science and engineering Co‐Innovation Center of Efficient Processing and Utilization of Forest ResourceNanjing Forestry UniversityNanjingJiangsuChina

The emergence of Li–Mg hybrid batteries has been receiving attention,owing to their enhanced electrochemical kinetics and reduced ***,the persistent challenge of uneven Mg electrodeposition remains a significant impediment to their practical ***,we developed an ingenious approach that centered around epitaxial electrocrystallization and meticulously controlled growth of magnesium crystals on a specialized MgMOF *** chosen MgMOF substrate demonstrated a robust affinity for magnesium and showed minimal lattice misfit with Mg,establishing the crucial prerequisites for successful heteroepitaxial ***,the incorporation of periodic electric fields and successive nanochannels within the MgMOF structure created a spatially confined environment that considerably promoted uniform magnesium nucleation at the molecular *** inspiration from the“blockchain”concept prevalent in the realm of big data,we seamlessly integrated a conductive polypyrrole framework,acting as a connecting“chain,”to interlink the“blocks”comprising the MgMOF *** innovative design significantly amplified charge‐transfer efficiency,thereby increasing overall electrochemical *** resulting architecture(MgMOF@PPy@CC)served as an exceptional host for heteroepitaxial Mg electrodeposition,showcasing remarkable electrostripping/plating kinetics and excellent cycling ***,a symmetrical cell incorporating the MgMOF@PPy@CC electrode demonstrated impressive stability even under ultrahigh current density conditions(10mAcm–2),maintaining operation for an extended 1200 h,surpassing previously reported ***,on coupling the MgMOF@PPy@CC anode with a Mo_(6)S_(8) cathode,the assembled battery showed an extended lifespan of 10,000 cycles at 70 C,with an outstanding capacity retention of 96.23%.This study provides a fresh perspective on the rational design of epitaxial electrocrystallizat

关键词： epitaxial electrodeposition lattice‐matching strategy Li-Mg hybrid batteries MOF substrate spatial confinement