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元启发式算法在植保无人机路径规划中的研究进展

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农机化研究 2025年第3期47卷 1-9页

作者：张旭东于丽娅李少波张安思张保贵州大学机械工程学院贵阳550025 贵州大学省部共建公共大数据国家重点实验室贵阳550025

随着无人机系统技术、传感器技术和人工智能算法等相关技术的不断发展,植保无人机路径规划技术在农业生产中备受重视,并被广泛应用。作为航空植保的关键技术之一,植保无人机路径规划面临的是一个复杂且多约束的组合优化问题。传统算法... 详细信息

随着无人机系统技术、传感器技术和人工智能算法等相关技术的不断发展,植保无人机路径规划技术在农业生产中备受重视,并被广泛应用。作为航空植保的关键技术之一,植保无人机路径规划面临的是一个复杂且多约束的组合优化问题。传统算法往往难以得到理想的结果,而元启发式算法则因其高效率成为解决该类优化问题的有效手段。为此,首先介绍了农业航空中的路径规划,随后总结出了植保无人机路径规划的关键要素,并使用更为合理的分类方式进行归纳;其次,从算法层面对相关研究所采用的元启发式算法进行分类和梳理,并阐述了其在实际应用中的现状,且根据提出的分类方法和研究特点,全面地归纳了当前的研究成果;最后,针对目前植保无人机路径规划研究存在的问题提出了几条可行的发展思路。

关键词：农机航空植保无人机路径规划元启发式算法乡村振兴农业现代化

Improving inherent soil productivity underpins agricultural sustainability

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Pedosphere 2023年第1期33卷 3-5页

作者： Jia bao zhang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China)

There is now increasing attention to how to raise global food production and security due to the expanding population *** and high yield of crops depends on soil quality improvement,which relies on inherent soil productivity *** in inherent soil productivity can provide a range of benefits for soil structure,microorganisms,nutrient cycling,and carbon *** underlying mechanisms related to inherent soil productivity improvement under different agricultural management practices on large scales need to be further ***,to achieve agricultural sustainability,efforts need to focus on developing technologies related to straw return,tillage management,and cover cropping and understanding their relationships with inherent soil productivity improvement.

关键词： soil crops return

Optimization Design of Minimum Total Resistance Hull Form Based on CFD Method

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China Ocean Engineering 2018年第3期32卷 323-330页

作者： zhang bao-ji zhang Sheng-long zhang Hui College of Ocean Science and Engineering Shanghai Maritime University Merchant Marine College Shanghai Maritime University

In order to reduce the resistance and improve the hydrodynamic performance of a ship, two hull form design methods are proposed based on the potential flow theory and viscous flow theory. The flow fields are meshed using body-fitted mesh and structured grids. The parameters of the hull modification function are the design variables. A three-dimensional modeling method is used to alter the geometry. The Non-Linear Programming(NLP) method is utilized to optimize a David Taylor Model Basin(DTMB) model 5415 ship under the constraints, including the displacement constraint. The optimization results show an effective reduction of the resistance. The two hull form design methods developed in this study can provide technical support and theoretical basis for designing green ships.

关键词： total resistance hull form design CFD technique Non-Linear Programming(NLP)

Preparation of single-phase ammonium dimolybdate by combination process

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Rare Metals 2012年第5期31卷 517-522页

作者： zhang bao XIA Xiaomei LI Qian School of Metallurgical Science and Engineering Central South University Changsha 410083 China

A novel method for the preparation of single-phase ammonium dimolybdate with industrial ammonium molybdate was studied. Various in- fluential factors were evaluated in the paper, including reaction temperature, reaction time, initial molybdenum concentration, initial NH_3 /Mo molar ratio, and stirring speed. Under the optimum experimental conditions, the crystallization rate of product is 85.23%. The X-ray diffraction (XRD) analysis and chemical analysis show that the product is single-phase ammonium dimolybdate, and no impurity phases exist. The scanning electronic microscope (SEM) image reveals uniform particle size, good particle dispersion, and no agglomeration between particles. Meanwhile, the final pH value of acidification was investigated. The total molybdenum recovery can reach up to 99.40%, and the main phases of acidification product are the same as those of raw material with the final pH value of 1.5. This determines that the acidification product can be used as a raw material to produce single-phase ammonium dimolybdate.

关键词： single-phase ammonium dimolybdate combination process crystallization rate phase composition total molybdenum recovery

Calculation Methods of Added Resistance and Ship Motion Response Based on Potential Flow and Viscous Flow Theory

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China Ocean Engineering 2022年第3期36卷 488-499页

作者： WU Qi-ming zhang bao-ji Shanghai Maritime University College of Ocean Science and EngineeringShanghai 201306China

To improve the energy efficiency of ships and to predict ship motion response under actual sea conditions,the far-field theory,strip theory,and Fujii and Takahashi’s modified semi-empirical method are based and studied to calculate the wave-induced added ***,a new modified formula based on the Maruo method is presented to calculate the radiation added resistance for the ship with a complex ***,some calculation details such as the Green function,the shape of the sections(shape below the still water level or shape below the wave level)in the strip theory,and so on are ***,the CFD method is used to simulate the motions of the hull and the added resistance,and the results of the CFD method and those of other numerical methods are analyzed and compared with the experiment *** modified method in the paper can predict the added resistance in waves for the complex-hull-surface ships well and quickly.

关键词： wave-induced added resistance strip theory computation fluid dynamics motion response

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： bao-Ri zhang Yong-Hua Shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection

Recent advances in improving performances of the lightweight complex hydrides Li-Mg-N-H system

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Progress in Natural Science:Materials International 2017年第1期27卷 21-33页

作者： bao zhang Ying Wu China Iron & Steel Research Institute Group Advanced Technology & Materials Co. Ltd

A brief review of state-of-the art advances in improving performances of the lightweight complex hydrides LiMg-N-H system is reported. Among the hydrogen storage materials, Li-Mg-N-H combination systems are regarded as one of the most potential candidates for the vehicular applications owing to their high hydrogen storage capacity( > 5 wt% H) and a more appropriate thermodynamic properties of hydrogen absorption and desorption. In the Li-Mg-N-H systems, tremendous efforts have been devoted to improving the hydrogen storage properties by adjusting composition, revealing reaction mechanisms, adding catalysts and refining the microstructures, etc. During the studies, different mechanisms, such as the coordinated two-molecule or multimolecule reaction mechanism and the ammonia-mediated mechanism, are proposed and applied under some certain conditions. Catalysis and nanosizing are very effective in enhancing the kinetic properties and thermodynamic destabilization of Li-Mg-N-H systems. Due to nano effects, the space-confinement and nanoconfinement seems to be more effective for improving the hydrogen storage performance, and it is great significant to develop hydrogen storage materials by studying the nanoconfined effects on the Li-Mg-N-H systems.

关键词： Li-Mg-N-H system Hydrogen storage Catalysis Nanosizing Mechanism

PARTICLE SWARM OPTIMIZATION BASED ON PYRAMID MODEL FOR SATELLITE MODULE LAYOUT

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Chinese Journal of Mechanical Engineering 2005年第4期18卷 530-536页

作者： zhang bao Teng Hongfei Key Laboratory for Precision and Nontraditional Machining Technology of Ministry of Education of China Dalian University of Technology Dalian 116024 China School of Mechanical Engineering Dalian University of Technology Dalian 116024 China

To improve the global search ability of particle swarm optimization （PSO）, a multi-population PSO based on pyramid model （PPSO） is presented. Then, it is applied to solve the layout optimization problems against the background of an international commercial communication satellite （INTELSAT-Ⅲ） module. Three improvements are developed, including multi-population search based on pyramid model, adaptive collision avoidance among particles, and mutation of degraded particles. In the numerical examples of the layout design of this simplified satellite module, the performance of PPSO is compared to global version PSO and local version PSO （ring and Neumann PSO）. The results show that PPSO has higher computational accuracy, efficiency and success ratio.

关键词： Particle swarm optimization Pyramid model Layout design Satellite module

Flight-Based Congestion Pricing Considering Equilibrium Flights in Airport Airside

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Journal of the Operations Research Society of China 2020年第3期8卷 477-491页

作者： bao-Cheng zhang School of Air Traffic Management Civil Aviation University of ChinaTianjin 300300China

Most of the previous works ignore the fact that equilibrium flights in self-profit maximization scenario are totally different from that in joint profit(social welfare)maximization scenario and take price difference(flight fare difference)between the two scenarios as congestion price,which is a passenger-based *** of all,the function of congestion pricing is to alleviate congestion by making airlines reduce flights at peak ***,the equilibrium flights under self-profit maximization should be the same as the ones under joint profit maximization after congestion prices are ***-based congestion pricing method is provided in our *** analysis suggests no role for congestion pricing when total real flight production of all airlines is less than the equilibrium flights under joint profit maximization ***,congestion tolls should be levied to all ***,congestion price can be determined by solving the corresponding equations system.

关键词： Flight-based congestion pricing Cournot game Equilibrium flight Passenger-based congestion pricing Aircraft type