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Uncertainty quantification of mechanism motion based on coupled mechanism—motor dynamic model for ammunition delivery system

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Defence Technology（防务技术） 2024年第3期33卷 125-133页

作者： Jinsong Tang Linfang Qian Longmiao Chen Guangsong Chen Mingming wang Guangzu Zhou Nanjing University of Science and Technology Nanjing 210094China Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099China

In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this *** main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the *** advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into *** simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified *** on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty *** work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system.

关键词： Ammunition delivery system Electromechanical coupling dynamics Uncertainty quantification Generalized probability density evolution

Pore-pressure and stress-coupled creep behavior in deep coal:Insights from real-time NMR analysis

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International Journal of Mining Science and Technology 2024年第1期34卷 77-90页

作者： Wenhao Jia Hongwei Zhou Senlin Xie Yimeng wang Xinfeng Hu Lei Zhang School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China School of Energy and Mining Engineering China University of Mining and Technology-BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology-BeijingBeijing 100083China College of Safety and Emergency Management Engineering Taiyuan University of TechnologyTaiyuan 030024China

Understanding the variations in microscopic pore-fracture structures(MPFS) during coal creep under pore pressure and stress coupling is crucial for coal mining and effective gas treatment. In this manuscript, a triaxial creep test on deep coal at various pore pressures using a test system that combines in-situ mechanical loading with real-time nuclear magnetic resonance(NMR) detection was ***-scale quantitative characterization, online real-time detection, and visualization of MPFS during coal creep influenced by pore pressure and stress coupling were performed using NMR and NMR imaging(NMRI) techniques. The results revealed that seepage pores and microfractures(SPM) undergo the most significant changes during coal creep, with creep failure gradually expanding from dense primary pore fractures. Pore pressure presence promotes MPFS development primarily by inhibiting SPM compression and encouraging adsorption pores(AP) to evolve into SPM. Coal enters the accelerated creep stage earlier at lower stress levels, resulting in more pronounced creep deformation. The connection between the micro and macro values was established, demonstrating that increased porosity at different pore pressures leads to a negative exponential decay of the viscosity coefficient. The Newton dashpot in the ideal viscoplastic body and the Burgers model was improved using NMR experimental results, and a creep model that considers pore pressure and stress coupling using variable-order fractional operators was developed. The model’s reasonableness was confirmed using creep experimental data. The damagestate adjustment factors ω and β were identified through a parameter sensitivity analysis to characterize the effect of pore pressure and stress coupling on the creep damage characteristics(size and degree of difficulty) of coal.

关键词： Real-time monitoring Pore pressure-stress coupling Microscopic pore-fracture structure Variable-order fractional creep model Deep coal

Large low-field reversible magnetocaloric effect in K_(3.Gd(PO_(4))_(2) at sub-Kelvin temperature

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Journal of Rare Earths 2024年第6期42卷 1087-1092,I0003页

作者： Haojie wang Zhaojun Mo Jianjian Gong Heng Tu Guochun Zhang Jun Shen School of Rare Earths University of Science and Technology of ChinaHefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China Center for Crystal Research and Development Key Laboratory of Functional Crystals and Laser TechnologyKey Laboratory of CryogenicsTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing100190China Department of Energy and PowerEngineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China

We synthesized a potassium gadolinium phosphate K3.d(PO_(4))_(2)with monoclinic structure(P2_(1/m))by the high-temperature solid-state reaction *** lattice constants obtained by Rietveld refinements of XRD curve are a=0.7411 nm,b=0.5624 nm,and c=0.943. *** and magnetocaloric properties of K_(3.Gd(PO_(4))_(2)were investigated in *** magnetic phase transition temperature of K3.d(PO_(4))2 was determined by ultra-low temperature testing to be 0.58 K.K_(3.Gd(PO_(4))2 exhibits large magnetic entropy changes(-ΔSM).The maximum-ΔSM are 20.2 and 29.4 J/(kg·K)in the magnetic field variation(ΔH)of 1 and 2 T,respectively,which are larger than that of the commercial Gd_(3.Ga_(5)O_(12)(GGG).The maximum adiabatic temperature change(ΔT_(ad))reaches 5.91 K under a magnetic field change(ΔH)of 1 T.K_(3.Gd(PO_(4))_(2)is a potential magnetic refrigeration material for obtaining sub-Kelvin temperatures.

关键词： Ultra-low temperature Magnetocaloric effect Magnetic entropy change Magnetic refrigeration Rare earths

Robust Reactive Power Scheduling of Distribution Networks Based on Modified Bootstrap Technique

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 154-166页

作者： Wenlong Liao Shouxiang wang Birgitte Bak-Jensen Jayakrishnan Radhakrishna Pillai Zhe Yang the AAU Energy Aalborg UniversityAalborg 9220Denmark the Key Laboratory of Smart Grid Ministry of EducationSchool of Electrical and Information EngineeringTianjin UniversityTianjin 300072China

The uncertainties of the power load,wind power,and photovoltaic power lead to errors between point prediction values and real values,which challenges the safe operation of distribution *** this paper,a robust reactive power scheduling(RRPS)model based on a modified bootstrap technique is proposed to consider the uncertainties of power loads and renewable energy ***,a deterministic reactive power scheduling(DRPS)model and an RRPS model are ***,a modified bootstrap technique is proposed to estimate prediction errors of power loads and renewable energy sources without artificially assuming the probability density function of prediction *** represent all possible scenarios,point prediction values and prediction errors are combined to construct two worst-case scenarios in the RRPS ***,the RRPS model is solved to find a scheduling scheme,which ensures the security of distribution networks for all possible scenarios in *** results show that the worst-case scenarios constructed by the modified bootstrap technique outperform popular ***,the RRPS model based on the modified bootstrap technique balances economics and security well.

关键词： Distribution network worst-case scenario robust programming prediction error bootstrap technique

Isotropic sintering shrinkage of 3. glass-ceramic nanolattices:backbone preforming and mechanical enhancement

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International Journal of Extreme Manufacturing 2024年第2期6卷 418-426页

作者： Nianyao Chai Yunfan Yue Xiangyu Chen Zhongle Zeng Sheng Li Xuewen wang Center of Femtosecond Laser Manufacturing for Advanced Materials and Devices State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070People’s Republic of China National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu LaboratoryFoshan 528000People’s Republic of China International School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070People’s Republic of China

There is a perpetual pursuit for free-form glasses and ceramics featuring outstanding mechanical properties as well as chemical and thermal *** is a promising idea to shape inorganic materials in three-dimensional(3.)forms to reduce their weight while maintaining high mechanical properties.A popular strategy for the preparation of 3. inorganic materials is to mold the organic–inorganic hybrid photoresists into 3. micro-and nano-structures and remove the organic components by subsequent ***,due to the discrete arrangement of inorganic components in the organic-inorganic hybrid photoresists,it remains a huge challenge to attain isotropic shrinkage during ***,we demonstrate the isotropic sintering shrinkage by forming the consecutive–Si–O–Si–O–Zr–O–inorganic backbone in photoresists and fabricating 3. glass–ceramic nanolattices with enhanced mechanical *** femtosecond(fs)laser is used in two-photon polymerization(TPP)to fabricate 3. green body *** subsequent sintering at 1000℃,high-quality 3. glass–ceramic microstructures can be obtained with perfectly intact and smooth ***-suit compression experiments and finite-element simulations reveal that octahedral-truss(oct-truss)lattices possess remarkable adeptness in bearing stress concentration and maintain the structural integrity to resist rod bending,indicating that this structure is a candidate for preparing lightweight and high stiffness glass–ceramic nanolattices.3. printing of such glasses and ceramics has significant implications in a number of industrial applications,including metamaterials,microelectromechanical systems,photonic crystals,and damage-tolerant lightweight materials.

关键词： 3. printing isotropic shrinkage femtosecond laser two-photon polymerization structural glass-ceramics

Progress of gaseous arsenic removal from flue gas by adsorption:Experimental and theoretical calculations

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Journal of Environmental Sciences 2024年第2期136卷 470-485页

作者： Xuelei Yan Qingzhu Li Xiaowei Huang Bensheng Li Shengtu Li Qingwei wang School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China National Engineering Research Center for Rare Earth Materials General Research Institute for Non-Ferrous MetalsBeijing 100088China

Because of its high mobility and difficult capture,gaseous arsenic pollution control has become the focus of arsenic pollution *** mainly exists in the form of highly toxic As_(2)O_(3.in the flue ***,removing gaseous As_(2)O_(3.from flue gas is of great practical significance for arsenic pollution *** gaseous As_(2)O_(3.on the surface of adsorbents by physical or chemical adsorption is an effective way to reduce the content of arsenic in the flue gas and alleviate arsenic *** the past few decades,various adsorbents have been developed to capture gaseous As_(2)O_(3.in the flue gas,and their adsorption mechanisms have been studied in ***,it is necessary to review the strategies of arsenic removal from flue gas by adsorption,which can inspire further *** on summarizing the morphological distribution of gaseous As_(2)O_(3.in the flue gas,this review further summarizes the removal of gaseous As_(2)O_(3.by several adsorbents and the effect of temperature and the main components of the flue gas on arsenic *** addition,the mechanism of arsenic removal based on adsorption in the flue gas is discussed in depth through theoretical calculations,which is the particular focus of this ***,prospects based on the present research state of arsenic removal by adsorption are proposed to provide ideas for developing effective and stable adsorbents for arsenic removal from flue gas.

关键词： Gaseous arsenic Flue gas Adsorption Theoretical calculation Mechanism

Towards complex scenes: A deep learning-based camouflaged people detection method for snapshot multispectral images

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Defence Technology（防务技术） 2024年第4期34卷 269-281页

作者： Shu wang Dawei Zeng Yixuan Xu Gonghan Yang Feng Huang Liqiong Chen School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

Camouflaged people are extremely expert in actively concealing themselves by effectively utilizing cover and the surrounding environment. Despite advancements in optical detection capabilities through imaging systems, including spectral, polarization, and infrared technologies, there is still a lack of effective real-time method for accurately detecting small-size and high-efficient camouflaged people in complex real-world scenes. Here, this study proposes a snapshot multispectral image-based camouflaged detection model, multispectral YOLO(MS-YOLO), which utilizes the SPD-Conv and Sim AM modules to effectively represent targets and suppress background interference by exploiting the spatial-spectral target information. Besides, the study constructs the first real-shot multispectral camouflaged people dataset(MSCPD), which encompasses diverse scenes, target scales, and attitudes. To minimize information redundancy, MS-YOLO selects an optimal subset of 12 bands with strong feature representation and minimal inter-band correlation as input. Through experiments on the MSCPD, MS-YOLO achieves a mean Average Precision of 94.3.% and real-time detection at 65 frames per second, which confirms the effectiveness and efficiency of our method in detecting camouflaged people in various typical desert and forest scenes. Our approach offers valuable support to improve the perception capabilities of unmanned aerial vehicles in detecting enemy forces and rescuing personnel in battlefield.

关键词： Camouflaged people detection Snapshot multispectral imaging Optimal band selection MS-YOLO Complex remote sensing scenes

Advancements in S-scheme heterojunction materials for photocatalytic environmental remediation

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Journal of Materials Science & Technology 2024年第2期169卷 182-198页

作者： Changliang Nie Xiaohan wang Ping Lu Yukun Zhu Xin Li Hua Tang School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao266071China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China School of Environmental Science and Engineering Shandong UniversityQingdao266237China

Recently,S-scheme heterojunctions have gained considerable attention in the field of photocatalytic environmental remediation as their potential to achieve efficient spatial charge separation coupled with strong redox ***,this review provides an overview of the current state-of-the-art in the development of S-scheme-based photocatalysts for the purification of environmental *** review first covers the fundamentals of heterogeneous photocatalysis for environmental ***,an introduction to the background,mechanism,design principles,and characterization techniques of S-scheme heterojunctions is ***,the review presents a comparison and summary of using various S-scheme photocatalysts for the removal of several target pollutants,such as bacteria,heavy metals,nitrogen oxides,antibiotics,and ***,the modification strategies of S-scheme heterojunction photocatalysts are also ***,a brief discussion of the challenges and prospects associated with S-scheme photocatalytic systems is demonstrated.

关键词： S-scheme heterojunctions Photocatalyst Pollutant Environmental remediation

High-Energy Tunable 6.5-12 μm Picosecond Mid-Infrared Radiation Generated from Optical Parametric Amplifier Based on LiInSe_(2) Crystal

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激光与光电子学进展 2024年第13期61卷 457-462页

作者： Zhang Jingjing wang Shilei Yang Feng wang Shanpeng Gao Hongwei Bo Yong Cui Dafu Tao Xutang Peng Qinjun Key Lab of Solid State Laser Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongChina

We report high-energy tunable 6.5-12 μm ps mid-infrared radiation generation based on OPA pumped using 1064 nm laser in LISe *** simulated the relationship between the idler energy and crystal *** optimum LISe length of 4 mm was used to enhance the idler energy *** a pump energy of ~9.4 mJ, energy levels of ~146 and of ~27 μJ are generated at 6.5 μm and 12 μm, *** highest energy of ~205 μJ is achieved at 8.1 μm at a pump energy of ~19 ***, the angular and spectral width acceptance are measured.

关键词： tunable mid-infrared radiation nonlinear optical crystal LiInSe2 crystal optical parametric amplifier