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RATIONAL GENERAL SOLUTIONS OF HIGHER ORDER ALGEBRAIC ODES

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Journal of Systems Science & Complexity 2013年第2期26卷 261-280页

作者： huang yanli NG L X Chu WINKLER Franz School of Computer Science and Software Engineering Tianjin Polytechnic University Research Institute for Symbolic Computation(RISC) Johannes Kepler University Department of Mathematics Quy Nhon University

This paper generalizes the method of Ng6 and Winkler （2010, 2011） for finding rational general solutions of a first order non-autonomous algebraic ordinary differential equation （AODE） to the case of a higher order AODE, provided a proper parametrization of its solution hypersurface. The authors reduce the problem of finding the rational general solution of a higher order AODE to finding the rational general solution of an associated system. The rational general solutions of the original AODE and its associated system are in computable 1-1 correspondence. The authors give necessary and sufficient conditions for the associated system to have a rational solution based on proper reparametrization of invariant algebraic space curves. The authors also relate invariant space curves to first integrals and characterize rationally solvable systems by rational first integrals.

关键词： Algebraic ODE associated system invariant algebraic space curve rational first integral rational general solution.

Multifunctional barium titanate ceramics via chemical modification tuning phase structure

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InfoMat 2020年第6期2卷 1163-1190页

作者： Chunlin Zhao yanli huang Jiagang Wu Department of Materials Science Sichuan UniversityChengduChina

Global environmental concerns on the toxicity of lead-based piezoelectrics impel the great mass fervor on investigations of lead-free *** titanate(BaTiO3,BT)ceramics,the first discovered perovskite ferroelectrics,were widely employed to fabricate dielectric capacitors from *** a piezoelectric breakthrough was achieved via chemical modification,intensive researches have been performed embracing lead-free BT-based piezoelectrics and their extensional *** this review,we encompass the stateof-the-art progress on chemical modification tuning phase structure toward advanced electrical properties in BT-based ***,modulated regularity of cations substitution on phase transition is summarized and ***,we highlight the common methodologies of phase structure(phase boundary,relaxor phase,room-temperature phase transition,etc.)design for optimizing piezoelectricity,electrostrictive strain,electrocaloric,dielectric energy storage or permittivity performances,and cover the noticeable developments and relevant physical ***,perspectives and challenges on future research issues are *** review proposes to exert the significant guidance and service for material design of BT-based and other lead-free perovskite materials with superior functionalities.

关键词： barium titanate-based ceramics chemical modification design methodologies electrical properties phase structure

Backfilling technology and strata behaviors in fully mechanized coal mining working face

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International Journal of Mining Science and Technology 2012年第2期22卷 151-157页

作者： Zhang Qiang Zhang Jixiong huang yanli Ju Feng School of Mines China University of Mining&TechnologyXuzhou 221116China State Key Laboratory of Coal Resources&Mine Safety Xuzhou 221008China

Based on the principle of fully mechanized backflling and coal mining technology and combined with the Xingtai Coal Mine conditions, we mainly optimized the coal mining equipment and adjusted the coal mining method in the Xingtai Coal Mine 7606 working face for implementation this technology. Firstly, we define the practical backfilling process as the ＂（from backfilling scraper conveyor＇s） head to tail back- filling, step by step swinging up of the tamping arm, gradual compacting, moving formed backfilling scra- per conveyor when the second tamping arm cannot pass and connecting the immediate roof by back material push front material movement＂. Meanwhile, the stress changes of backfill body in coal mined out area was monitored by stress sensors, and the roof caving law was analyzed by monitoring the dynamic subsidence of -210 west roadway of this face. The site tests results show that using this new backfilling and coal mining integrated technology, the production capacity in the 7606 working face can reach to 283,000 ton a year, and 282,000 ton of solid materials （waste and fly ash） is backfilled, which meets the needs of high production and efficiency. The goaf was compactly backfilled with solid material and the strata behavior was quite desirable, with an actual maximum vertical stress of the backfill body of 5.5 MPa. Backfill body control the movement of overburden within a certain range, and there is no col- lapses of major areas in the overlying strata upon backfilled gob. The maximum subsidence and speed were 231 mm and 15.75 mm/d respectively, which proved the practical significance of this integrated technology.

关键词： Fully mechanized backfilling and coalmining technologyHydraulic supportFormed backfilling scraper conveyorBackfilling technologyStrata behaviors

Loose Gangues Backfill Body’s Acoustic Emissions Rules During Compaction Test:Based on Solid Backfill Mining

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Computer Modeling in Engineering & Sciences 2018年第4期115卷 85-103页

作者： Junmeng Li yanli huang Wenyue Qi Guoqiang Kong Tianqi Song State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining&TechnologyXuzhou 221116China

In fully mechanized solid backfilling mining(FMSBM),the loose gangues backfill body(LGBB)that filled into the goaf becomes the main body of bearing the overburden *** deformation resistance of LGBB is critical for controlling overburden movement and surface *** the process of load bearing,LGBB will experience grain crushing,which has a significant effect on its deformation *** block will be accompanied with obvious acoustic emissions(AE)features in process of slipping,flipping and *** confined compression test,monitoring the AE parameters of LGBB can reveal the impact mechanism of grain crushing on LGBB *** study is of great significance for obtaining an in-depth understanding of the mechanical properties of LGBB,and providing guidance to the engineering practice of *** order to study the rules of acoustic emissions(AE)of graded Loose gangues backfill body(LGBB)in confined compression test,this article introduces the AE systems to conventional confined compression test to monitor AE signals resulted from the friction and fragmentation among *** test results show that in the process of LGBB compaction,AE parameters are highly correlated with the strain-stress *** events of balanced-sized graded gangues are more inactive than other two graded samples in different compression stages,AE events of large-particle-dominated graded gangues are most *** the spatial distribution,AE events are the most active on the edges and the middle part of test samples and the phenomenon of grain crushing is the most obvious in these positions.

关键词： Loose gangues backfill body Confined compression acoustic emission spacetime evolution failure mechanism

文旅融合背景下肇庆市夜经济发展潜力及策略研究

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肇庆学院学报 2025年第1期46卷 100-106页

作者：吴清钟佳珊张莉婷黄衍丽肇庆学院发展规划部广东肇庆526061 肇庆学院旅游与历史文化学院广东肇庆526061

夜经济作为经济社会高质量发展的新亮点,是促消费稳增长的重要动力引擎,有效推动了旅游经济的增长。肇庆市重视扩大夜间经济活动的规模及影响力,打造系列深受居民和游客喜爱的夜间文化项目、夜游街区、夜间经济集聚区。文章分析文旅融... 详细信息

夜经济作为经济社会高质量发展的新亮点,是促消费稳增长的重要动力引擎,有效推动了旅游经济的增长。肇庆市重视扩大夜间经济活动的规模及影响力,打造系列深受居民和游客喜爱的夜间文化项目、夜游街区、夜间经济集聚区。文章分析文旅融合背景下肇庆市夜间经济发展的现状及挑战,提出推动肇庆市夜间经济高质量发展的对策建议。研究表明:肇庆市夜经济发展具有较大的文化潜力、旅游潜力、社会发展潜力,但仍面临市场环境、文化特色、旅游效应、政策等方面问题。建议从政府引领、文化内涵和区域业态等方面激发新的增长动力。

关键词：夜经济文旅融合发展潜力优化策略肇庆市

Huge thick conglomerate movement induced by full thick longwall mining huge thick coal seam

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International Journal of Mining Science and Technology 2012年第3期22卷 399-404页

作者： Ma Liqiang Qiu xiaoxiang Dong Tao Zhang Jixiong huang yanli School of Mines China University of Mining & Technology Xuzhou 221116 China State Key Laboratory of Coal Resources & Mine Safety Xuzhou 221008 China China Yongcheng Coal and Electric Power Group Corporation Ltd. Yongcheng 476600 China

A discrete elemental method was used to study the thickness of conglomerate layer in a full thick seam mining activities under the influence of the law, pointing out the thickness of the conglomerate at different seam mining, and during the destruction and instability of existing state of laws. At 21141 thick seam mining, the face toward the direction of separation between the thick layer of conglomerate rock and the next bit after reaching its maximum capacity due to pull from the bottom of the plastic zone, formed a stratified and hierarchical down collapse. The shape of caving area is a ''triangular block'', the length of the plastic zone and face advancement from the linear fit between the height of the plastic zone and the advancing face is a quadratic function of distance, while the top layer of thick gravel layer is the overall bending subsidence trend. Tilting the direction of the face, a thick gob of collapsed conglomerate layer is formed in the coal gob entity on both sides of the thick conglomerate at the top of the overall fracture morphology performance, thus forming a mutual extrusion of articulated block structure. The instability, separation and balance of the thick conglomerate layer in the hinged block stope stress leads to abnormal occurrence of rock burst induced by face as the major factor in the accident. This research reveals the form of stress distribution in the destroyed layer of the thick conglomerate rock, analyzes the stope law of coupling for the pressure burst behavior law for the mining work face, and the choice of preventive measures to provide a theoretical basis and implementation.

关键词： Huge thick conglomerateHuge thick coal seamSeparationCollapseRock burst

Experiment on acoustic emission response and damage evolution characteristics of polymer-modified cemented paste backfill under uniaxial compression

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International Journal of Minerals,Metallurgy and Materials 2023年第8期30卷 1502-1514页

作者： Shenyang Ouyang yanli huang Nan Zhou Ming Li Xiaotong Li Junmeng Li Fei Ke Yahui Liu State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining and TechnologyXuzhou 221116China Xinjiang Institute of Engineering Urumqi 830000China Henan Energy Chemical Group Co. Ltd.Zhengzhou 450000China

The mechanical properties of cemented paste backfill(CPB)determine its control effect on the goaf *** this study,the mechanical strength of polymer-modified cemented paste backfill(PCPB)samples was tested by uniaxial compression tests,and the failure characteristics of PCPB under the compression were ***,acoustic emission(AE)technology was used to monitor and record the cracking process of the PCPB sample with a curing age of 28 d,and two AE indexes(rise angle and average frequency)were used to classify the failure modes of samples under different loading *** results show that waterborne epoxy resin can significantly enhance the mechanical strength of PCPB samples(when the mass ratio of polymer to powder material is 0.30,the strength of PCPB samples with a curing age of 28 d is increased by 102.6%);with the increase of polymer content,the mechanical strength of PCPB samples is improved significantly in the early and middle period of *** uniaxial load,the macro cracks of PCPB samples are mostly generated along the axial direction,the main crack runs through the sample,and a large number of small cracks are distributed around the main *** AE response of PCPB samples during the whole loading process can be divided into four periods:quiet period,slow growth period,rapid growth period,and remission period,corresponding to the micro-pore compaction stage,elastic deformation stage,plastic deformation stage,and failure instability stage of the stress-strain *** AE events are mainly concentrated in the plastic deformation stage;both shear failure and tensile failure occur in the above four stages,while tensile failure is dominant for PCPB *** study provides a reference for the safety of coal pillar recovery in pillar goaf.

关键词： polymer cemented paste backfill mechanical strength acoustic emission

An investigation of surface deformation after fully mechanized,solid back fill mining

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International Journal of Mining Science and Technology 2012年第4期22卷 453-457页

作者： Li Jian Zhang Jixiong huang yanli Zhang Qiang Xu Junming School of Mines.China University of Mining&Technology Xuzhou 221008ChinaState Key Laboratory of Coal Resources and Mine SafetyXuzhou 221008China

The surface deformation after fully mechanized back filling mining was *** surface deformation for different backfill materials was predicted by an equivalent mining height model and numerical *** results suggest that:(1) As the elastic modulus,E,of the backfill material increases the surface subsidence *** rate of subsidence decrease drops after E is larger than 5 GPa;(2) Fully mechanized back fill mining technology can effectively control surface *** resulting surface deformation is within the specification grade I,which means surface maintenance is not needed.A site survey showed that the equivalent mining height model is capable of predicting and analyzing surface deformation and that the model is conservative enough for engineering ***,the significance of establishing a complete error correction system based on error analysis and correction is discussed.

关键词： Back filling mining Back filling materials Surface deformation Equivalent mining height

Transparent characterization and quantitative analysis of broken gangue's 3D fabric under the bearing compression

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International Journal of Mining Science and Technology 2022年第2期32卷 335-345页

作者： Junmeng Li yanli huang Shenyang Ouyang Yachao Guo Huadong Gao Laiwei Wu Yibing Shi Lei Zhu State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining&TechnologyXuzhou 221116China Key Laboratory of Deep Coal Resource Mining of Ministry of Education China University of Mining&TechnologyXuzhou 221116China College of Mining Engineering and Geology Xinjiang Institute of EngineeringUrumqi 830000China CT Room Xuzhou Central HospitalXuzhou 221009China

Broken gangue has been extensively used in rockfill dams,subgrade,embankment,foundation cushion and other engineering *** deformation characteristics of broken gangue under the bearing compression play a decisive role in the firmness,stability and safety of these structures(buildings),and the meso-fabric change of broken gangue under the bearing compression significantly affects its macro *** this study,the transparent characterization and quantitative analysis of 3D fabric of broken gangue under the bearing compression were performed through CT scanning test,image processing and 3D reconstruction technology,and the influence mechanism of internal fabric of broken gangue on its macro deformation was *** results show that:In the loading stage of 0–2 MPa,the sharp corners,thin edges on the blocks and the bar-shaped and blade-shaped blocks with poor regularity are broken first under the bearing compression;in the loading stage of 2–8 MPa,a large number of larger particles in the sample are crushed in the mode of fragmentation;in the loading stage of 8–10 MPa,the breakage degree of samples is *** axial displacement of the block inside the sample occurs,as well as the lateral displacement of the block converging to the central axis of the *** the rapid deformation stage,the macro deformation of the broken gangue is mainly caused by the rearrangement and adjustment of the block structure and the breakage of the block;in the slow deformation stage,it is mainly caused by the breakage of the block;in the stable deformation stage,it is mainly caused by the optimization and adjustment of the bearing skeleton in the sample.

关键词： Bearing compression Broken gangue 3D fabric Transparent characterization Quantitative analysis