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煤层瓦斯抽采爆破卸压的钻孔布置优化分析及应用

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岩石力学与工程学报 2013年第4期32卷 807-813页

作者：周声才李栋张凤舞沈大富周东平郭臣业重庆市能源投资集团重庆401121 重庆市能源投资集团科技有限责任公司重庆400060 重庆大学煤矿灾害动力学与控制国家重点实验室重庆400030

为解决重庆地区低透气性松软煤层瓦斯抽采率低的难题,提出煤层底板预裂爆破卸压增透新技术,指出其增透过程分为爆破应力波与爆生气体共同作用形成裂隙贯通区和爆破空腔顶部煤岩体垮落形成卸压带2个阶段。借助数值模拟对不同孔距爆破应... 详细信息

为解决重庆地区低透气性松软煤层瓦斯抽采率低的难题,提出煤层底板预裂爆破卸压增透新技术,指出其增透过程分为爆破应力波与爆生气体共同作用形成裂隙贯通区和爆破空腔顶部煤岩体垮落形成卸压带2个阶段。借助数值模拟对不同孔距爆破应力波的动态演变规律进行研究,发现预裂爆破影响范围分为粉碎区和贯通区,其中粉碎区范围约为爆破孔直径的6倍,而贯通区的形成则主要受大直径控制孔反射形成的拉伸波作用,最终得到预裂爆破形成贯穿裂隙且保持与控制孔同高破坏区间的最优孔距为0.9 m,并将该技术应用于重庆–煤矿K4煤层底板巷预抽瓦斯工程。应用结果表明:瓦斯抽采纯量提高2.8倍,瓦斯抽采浓度提高3.75倍,而且在爆破完成20～30 d后瓦斯抽采效果明显提高。

关键词：采矿工程低透气性松软煤层爆破卸压钻孔间距数值分析应力波

中职学校“电子技能与实训”课程教学改革与实践

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现代信息科技 2019年第20期3卷 191-193页

作者：周胜彩湖南省永州市工业贸易中等专业学校

"电子技能与实训"是中等职业学校电子类及相关专业的一门重要的专业基础课程,在实际教学过程中,创新教学工作思路,注重学生个性发展,充分发挥学生的主体作用,内容紧扣中职教材与时代发展需求,不断改革与创新。学生通过对本课程的学习,... 详细信息

"电子技能与实训"是中等职业学校电子类及相关专业的一门重要的专业基础课程,在实际教学过程中,创新教学工作思路,注重学生个性发展,充分发挥学生的主体作用,内容紧扣中职教材与时代发展需求,不断改革与创新。学生通过对本课程的学习,可获得电子技术领域的基本理论、基本知识和基本技能,学会运用所学知识分析问题和解决实际问题,不断提高专业技能和综合素养,为今后专业课的学习以及就业与创业奠定坚实的理论和实践基础。

关键词：电子技能与实训课程教学改革与实践

Parallel Physics-Informed Neural Networks Method with Regularization Strategies for the Forward-Inverse Problems of the Variable Coefficient Modified KdV Equation

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Journal of Systems Science & Complexity 2024年第2期37卷 511-544页

作者： zhou Huijuan School of Science Shanghai Maritime UniversityShanghai 201306China

This paper mainly introduces the parallel physics-informed neural networks(PPINNs)method with regularization strategies to solve the data-driven forward-inverse problems of the variable coefficient modified Korteweg-de Vries(VC-MKdV)*** the forward problem of the VC-MKdV equation,the authors use the traditional PINN method to obtain satisfactory data-driven soliton solutions and provide a detailed analysis of the impact of network width and depth on solving accuracy and ***,the author finds that the traditional PINN method outperforms the one with locally adaptive activation functions in solving the data-driven forward problems of the VC-MKdV *** for the data-driven inverse problem of the VC-MKdV equation,the author introduces a parallel neural networks to separately train the solution function and coefficient function,successfully addressing the function discovery problem of the VC-MKdV *** further enhance the network’s generalization ability and noise robustness,the author incorporates two regularization strategies into the *** amount of numerical experimental data in this paper demonstrates that the PPINNs method can effectively address the function discovery problem of the VC-MKdV equation,and the inclusion of appropriate regularization strategies in the PPINNs can improves its performance.

关键词： Data-driven forward-inverse problems parallel physics-informed neural networks regularization strategies variable coefficient modified KdV equation

Influence of stearic acid surface modification on flowability and agglomeration of battery grade Li2CO3 powder

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颗粒学报（英文版） 2024年第9期92卷 263-277页

作者： Ming zhou Lithium Industry Center Zhejiang New Era Zhongneng Technology Co.Ltd.Shaoxing312000China

This work investigates the flow and agglomeration behaviors of battery grade Li2CO3 powder and the influence of stearic acid surface *** degree of agglomeration is directly related to the uniformity of Li2CO3 and its powder *** to the Chinese National Nonferrous Metal In-dustry Standard,battery grade Li2CO3 powder has D50 equal to 3-8 μm which belongs to a micron-sized superfine ***,with the extension of storage time,the serious agglomeration phenomenon occurs due to the large specific surface area and rough and irregular powder *** Hausner ratio(HR)of the unmodified sample increases from 1.14 to 1.41,and the corresponding flowability is classified as good to ***,among samples with doping stearic acid,the optimum amount of it is 0.10 wt％which exhibits an extremely stable HR value from 1.14 to ***,after 156 days,the repose angle(AR)obtained for samples without surface modification and using 0.10 wt％stearic acid are calculated to be 49° and 28°,*** on the values of HR and AR,the flowability of the unmodified sample is poor while the sample modified with 0.10 wt％of stearic acid still maintain excellent powder flow ***,The LiMn2O4 cathode material synthesized from modified Li2CO3 powder with a stearic acid content of 0.10 wt％exhibits good crystallinity and comparable elec-trochemical performance to that prepared by commercial *** results indicate that stearic acid has the potential to be an ideal modifier for battery grade Li2CO3 powder that needs to be kept for a long time.

关键词： Battery grade Li2CO3 powder Flowability Stearic acid Surface modification

Deep-reinforcement-learning-based UAV autonomous navigation and collision avoidance in unknown environments

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Chinese Journal of Aeronautics 2024年第3期37卷 237-257页

作者： Fei WANG Xiaoping ZHU zhou zhou Yang TANG School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

In some military application scenarios,Unmanned Aerial Vehicles(UAVs)need to perform missions with the assistance of on-board cameras when radar is not available and communication is interrupted,which brings challenges for UAV autonomous navigation and collision *** this paper,an improved deep-reinforcement-learning algorithm,Deep Q-Network with a Faster R-CNN model and a Data Deposit Mechanism(FRDDM-DQN),is proposed.A Faster R-CNN model(FR)is introduced and optimized to obtain the ability to extract obstacle information from images,and a new replay memory Data Deposit Mechanism(DDM)is designed to train an agent with a better *** training,a two-part training approach is used to reduce the time spent on training as well as retraining when the scenario *** order to verify the performance of the proposed method,a series of experiments,including training experiments,test experiments,and typical episodes experiments,is conducted in a 3D simulation *** results show that the agent trained by the proposed FRDDM-DQN has the ability to navigate autonomously and avoid collisions,and performs better compared to the FRDQN,FR-DDQN,FR-Dueling DQN,YOLO-based YDDM-DQN,and original FR outputbased FR-ODQN.

关键词： Faster R-CNN model Replay memory Data Deposit Mechanism(DDM) Two-part training approach Image-based Autonomous Navigation and Collision Avoidance(ANCA) Unmanned Aerial Vehicle(UAV)

Oxidation of emerging organic contaminants by in-situ H_(2)O_(2) fenton system

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Green Energy & Environment 2024年第3期9卷 417-434页

作者： Yuqin Ni Chuxiang zhou Mingyang Xing Yi zhou State Environmental Protection Key Lab of Environmental Risk Assessment and Control on Chemical Processes School of Resources&Environmental EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Advanced Materials and Institute of Fine Chemicals National Engineering Laboratory for Industrial Wastewater TreatmentSchool of Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237China Department of Applied Natural Sciences Technische Hochschule LubeckMonkhofer Weg 23923562 LubeckGermany

The existence and risk of emerging organic contaminants(EOCs)have been under consideration and paid much effort to degrade these *** system is one of the most widely used technologies to solve this *** original Fenton system relies on the hydroxyl radicals produced by Fe(Ⅱ)/H_(2)O_(2) to oxidize the organic ***,the application of the Fenton system is limited by its low iron cycling efficiency and the high risks of hydrogen peroxide transportation and *** introduction of external energy(including light and electricity etc.)can effectively promote the Fe(Ⅲ)/Fe(Ⅱ)cycle and the reduction of oxygen to produce hydrogen peroxide in *** review introduces three in-situ Fenton systems,which are electro-Fenton,Photo-Fenton,and chemical *** mechanism,influencing factors,and catalysts of these three in-situ Fenton systems in degrading EOCs are discussed *** review strengthens the understanding of Fenton and in-situ Fenton systems in degradation,offering further insight into the real application of the in-situ Fenton system in the removal of EOCs.

关键词： In-situ H_(2)O_(2)production Fenton Emerging organic contaminants Photocatalysis Electrocatalysis

SPARSE RECOVERY BASED ON THE GENERALIZED ERROR FUNCTION

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Journal of Computational Mathematics 2024年第3期42卷 679-704页

作者： Zhiyong zhou Department of Statistics and Data Science and Institute of Digital FinanceHangzhou City UniversityHangzhou 310015China

In this paper,we offer a new sparse recovery strategy based on the generalized error *** introduced penalty function involves both the shape and the scale parameters,making it extremely *** both constrained and unconstrained models,the theoretical analysis results in terms of the null space property,the spherical section property and the restricted invertibility factor are *** practical algorithms via both the iteratively reweighted■_(1)and the difference of convex functions algorithms are *** experiments are carried out to demonstrate the benefits of the suggested approach in a variety of *** practical application in magnetic resonance imaging(MRI)reconstruction is also investigated.

关键词： Sparse recovery Generalized error function Nonconvex regularization Itera-tive reweighted Li Difference of convex functions algorithms

Emergent Geometry of KP Hierarchy

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Acta Mathematica Sinica,English Series 2024年第1期40卷 3-25页

作者： Jian zhou Department of Mathematical Sciences Tsinghua UniversityBeijng 100084P.R.China

We explain how to construct a quantum deformation of a spectral curve associated to a tau-function of the KP *** construction is applied to Witten-Kontsevich tau-function to give a natural explanation of some earlier ... 详细信息

关键词： KP hierarchy tau-functions spectral curves

The dry-hot feedback between soil moisture and atmosphere and the accelerated global warming

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Science China Earth Sciences 2024年第3期67卷 890-891页

作者： Tianjun zhou State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Greenhouse gas (GHG) emissions have been increasing due to human activities since the Industrial Revolution, resulting in continuous warming of the global climate system and significant drought over a large parts of global land, both have shown a non-linear growth trend in recent decades(Berg et al., 2017;zhou et al., 2019;IPCC, 2021).

关键词： warming moisture drought