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基于注汞法的液冷花岗岩微观特性实验研究

Journal of Central South University 2024年第1期31卷 169-181页

作者：尹土兵苏巨振庄登登李夕兵 School of Resources and Safety Engineering Central South UniversityChangsha 410083China Oulu Mining School University of OuluFI-90014 OuluFinland

在开采高温储层的过程中,微观特征变化重要影响深部热储层人工裂隙网络的建立。因此,研究该过程中微观特征的变化对深部地热能的安全高效开采具有重要意义。采用液体冷却(包括酸冷却和水冷却)处理高温花岗岩,模拟向高温储层注酸情况,以... 详细信息

在开采高温储层的过程中,微观特征变化重要影响深部热储层人工裂隙网络的建立。因此,研究该过程中微观特征的变化对深部地热能的安全高效开采具有重要意义。采用液体冷却(包括酸冷却和水冷却)处理高温花岗岩,模拟向高温储层注酸情况,以获取相应条件下的花岗岩试样。随后,使用扫描电子显微镜-能量散射谱(SEM-EDS)和高压注汞法对样品进行测试。SEM-EDS结果显示,水冷却几乎不会影响元素的组成,酸冷却导致氧、硅和金属元素减少。在两种情况下,都观察到了孔隙和裂缝的形成。此外,与水冷却相比,酸冷却的样品表面更加不平整、疏松和粗糙。注汞法测试结果显示,随着处理温度的升高,液冷花岗岩样品的孔隙率、孔隙体积和比表面积有增加,但分形维数呈相反的趋势。研究结果表明,与水冷却相比,酸冷却条件对花岗岩的腐蚀作用使各项参数的变化更加显著,在酸冷却过程中产生更多的孔隙,提供更好的运输空间,使孔隙结构的复杂性降低。在高温储层的地热能有效提取方面,酸冷却具有更大应用潜力。

关键词：孔隙结构微观结构液体冷却土酸溶液注汞法花岗岩分形理论

Effects of thermal treatment on physical and mechanical characteristics of coal rock

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Journal of Central South University 2016年第9期23卷 2336-2345页

作者： yin tu-bing WANG Pin LI Xi-bing SHU Rong-hua YE Zhou-yuan School of Resources and Safety Engineering Central South University Changsha 410083 China School of Energy and Safety Engineering Hunan University of Science and Technology Xiangtan 411201 China

To study the physical and mechanical properties of coal rock after treatment at different temperatures under impact loading, dynamic compression experiments were conducted by using a split Hopkinson pressure bar(SHPB). The stress–strain curves of specimens under impact loading were obtained, and then four indexes affected by temperature were analyzed in the experiment: the longitudinal wave velocity, elastic modulus, peak stress and peak strain. Among these indexes, the elastic modulus was utilized to express the specimens' damage characteristics. The results show that the stress–strain curves under impact loading lack the stage of micro-fissure closure and the slope of the elastic deformation stage is higher than that under static loading. Due to the dynamic loading effect, the peak stress increases while peak strain decreases. The dynamic mechanical properties of coal rock show obvious temperature effects. The longitudinal wave velocity, elastic modulus and peak stress all decrease to different extents with increasing temperature, while the peak strain increases continuously. During the whole heating process, the thermal damage value continues to increase linearly, which indicates that the internal structure of coal rock is gradually damaged by high temperature.

关键词： rock mechanical property split Hopkinson pressure bar (SHPB) high temperature coal rock dynamic mechanical property

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多矿区整合条件下矿井通风系统优化方案研究

世界有色金属 2024年第4期 63-67页

作者：马鹏飞王建兵李拥军黄富邦李帅尹土兵甘肃洛坝有色金属集团有限公司甘肃徽县742312 中南大学资源与安全工程学院湖南长沙410083

洛坝铅锌矿作为一个多矿区整合矿山,地表坑口众多、巷道纵横交错、井下作业点多面广、采空区规模庞大,导致井下污风串联严重、风流紊乱,通风效果较差。通过通风线路调查、矿井需风量计算和基于Ventsim的通风网络解算,进行了针对性的多... 详细信息

洛坝铅锌矿作为一个多矿区整合矿山,地表坑口众多、巷道纵横交错、井下作业点多面广、采空区规模庞大,导致井下污风串联严重、风流紊乱,通风效果较差。通过通风线路调查、矿井需风量计算和基于Ventsim的通风网络解算,进行了针对性的多矿区整合条件下矿井通风系统整合优化方案研究,改善了井下风流治理、提高了通风效果。

关键词：整合矿山漏风串风通风系统优化

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矿区整合条件下复杂开拓系统整合优化方案研究

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世界有色金属 2024年第6期 30-33页

作者：黄富邦王建兵李拥军李帅张钦礼尹土兵甘肃洛坝有色金属集团有限公司甘肃徽县742312 中南大学资源与安全工程学院湖南长沙410083

洛坝铅锌矿作为一个多矿区整合矿山,现有的多坑口组织生产、多级斜井提升、井下作业点多面广,导致井下作业人员越多、提升运输成本高效率低等突出问题。通过提出四种开拓系统整合优化方案并进行了详细的技术经济对比,最终优选了以盲竖... 详细信息

洛坝铅锌矿作为一个多矿区整合矿山,现有的多坑口组织生产、多级斜井提升、井下作业点多面广,导致井下作业人员越多、提升运输成本高效率低等突出问题。通过提出四种开拓系统整合优化方案并进行了详细的技术经济对比,最终优选了以盲竖井、箕斗斜井和斜坡道为核心的运输系统方案打破各坑口各自为政的生产现状,将矿山整合为一体进行集中提升运输,提高了运输效率、减少了用工数量、节约提升成本、降低了管理难度。

关键词：整合矿山多级提升开拓系统优化

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Acoustic emission characteristics of rock under impact loading

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Journal of Central South University 2015年第9期22卷 3571-3577页

作者：刘希灵李夕兵洪亮尹土兵饶蒙 School of Resources and Safety Engineering Central South University Norman B. Keevil Institute of Mining Engineering University of British Columbia School of Civil Engineering Hunan City University

Acoustic emission tests were performed using a split Hopkinson pressure bar system(SHPB) on 50-mm-diameter bars of granite, limestone, sandstone and skarn. The results show that the amplitude distribution of hits is not well centralized around 50 d B, and that some hits with large amplitudes, usually larger than 70 d B, occur in the early stages of each test, which is different from the findings from static and low-loading-rate tests. Furthermore, the dominant frequency range of the recorded acoustic emission waveforms is between 300 k Hz and 500 k Hz, and frequency components higher than 500 k Hz are not significant. The hit with the largest values of amplitude, counts, signal strength, and absolute energy in each test, displays a waveform with similar frequency characteristics and greater correlation with the waveform obtained from the elastic input bar of the split Hopkinson pressure bar system compared with the waveforms of the other hits. This indicates that the hit with the largest values of amplitude, counts, signal strength, and absolute energy is generated by elastic wave propagation instead of fracture within the rock specimen.

关键词： rock acoustic emission(AE) split Hopkinson pressure bar(SHPB) hit driven features frequency characteristics correlation analysis

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轴压和围压对循环冲击下砂岩能量耗散的影响

岩土力学 2013年第11期34卷 3096-3102,3109页

作者：金解放李夕兵殷志强尹土兵江西理工大学建筑与测绘工程学院江西赣州341000 中南大学资源与安全工程学院长沙410083 安徽理工大学能源与安全学院安徽淮南232001

利用动静组合加载试验装置,对具有不同轴压和围压的砂岩进行循环冲击试验,研究循环冲击过程中砂岩单位体积吸收能的变化特性、单位体积吸收能与平均应变率的关系以及轴压和围压对循环冲击作用下岩石能量耗散的影响。围压分别设置为4、8... 详细信息

利用动静组合加载试验装置,对具有不同轴压和围压的砂岩进行循环冲击试验,研究循环冲击过程中砂岩单位体积吸收能的变化特性、单位体积吸收能与平均应变率的关系以及轴压和围压对循环冲击作用下岩石能量耗散的影响。围压分别设置为4、8、10、12 MPa等4个系列,轴向静载荷分别设置为49、84、105、125 MPa等4个系列,入射杆上的入射波峰值大小近似相等,入射能大小为230 J。研究结果表明,砂岩单位体积吸收能随循环冲击次数的增加而增加。平均应变率和单位体积吸收能具有良好的正线性关系,围压从低到高增加过程中,二者间拟合直线的斜率K随轴压增加的变化关系为"增加-基本不变-减小"。当轴压较小时,K随围压的增加先增加后降低,轴压越小K由上升到下降转折点处的围压越大;当轴压增加到125 MPa时,K随围压的增加始终降低。研究结果为具有不同地应力条件下工程岩体爆破设计提供理论依据。

关键词：循环冲击轴压围压能量耗散影响

SWG: an architecture for sparse weight gradient computation

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Science China(Information Sciences) 2024年第2期67卷 302-321页

作者： Weiwei WU Fengbin tu Xiangyu LI Shaojun WEI Shouyi yin School of Integrated Circuits Tsinghua University Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology

On-device training for deep neural networks(DNN) has become a trend due to various user preferences and scenarios. The DNN training process consists of three phases, feedforward(FF), backpropagation(BP), and weight gradient(WG) update. WG takes about one-third of the computation in the whole training process. Current training accelerators usually ignore the special computation property of WG and process it in a way similar to FF/BP. Besides, the extensive data sparsity existing in WG, which brings opportunities to save computation, is not well explored. Nevertheless, exploiting the optimization opportunities would meet three underutilization problems, which are caused by(1) the mismatch between WG data dimensions and hardware parallelism,(2) the full sparsity, i.e., the sparsity of feature map(Fmap),error map(Emap), and gradient, and(3) the workload imbalance resulting from irregular sparsity. In this paper, we propose a specific architecture for sparse weight gradient(SWG) computation. The architecture is designed based on hierarchical unrolling and sparsity-aware(HUSA) dataflow to exploit the optimization opportunities of the special computation property and full data sparsity. In HUSA dataflow, the data dimensions are unrolled hierarchically on the hardware architecture. A valid-data trace(VDT) mechanism is embedded in the dataflow to avoid the underutilization caused by the two-sided input sparsity. The gradient is unrolled in PE to alleviate the underutilization induced by output sparsity while maintaining the data reuse opportunities. Besides, we design an intra-and inter-column balancer(IIBLC) to dynamically tackle the workload imbalance problem resulting from the irregular sparsity. Experimental results show that with HUSA dataflow exploiting the full sparsity, SWG achieves a speedup of 12.23× over state-of-the-art gradient computation architecture, Train Ware. SWG helps to improve the energy efficiency of the state-of-the-art training accelerator LNPU from

关键词： CNN training gradient computation sparsity architecture

Study on the performance of lightweight roadway wall thermal insulation coating containing EP-GHB mixed ceramsite

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Building Simulation 2024年第5期17卷 785-798页

作者： Yongliang Zhang Shili yin Hongwei Mu Xilong Zhang Qinglei Tan bing Shao Key Lab of Industrial Fluid Energy Conservation and Pollution Control Ministry of EducationQingdao University of TechnologyQingdaoShandong266520China College of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdaoShandong266520China

As the mining depth increases,the problem of high-temperature thermal damage mainly caused by heat dissipation of surrounding rock is becoming more and more *** is very important to solve the environmental problem of mine heat damage to improve the efficiency of mineral resource exploitation and protect the physical and mental health of *** can apply thermal insulation coating on the walls of mine roadways as a means of implementing active heat *** this paper,expanded perlite(EP)and glazed hollow bead(GHB)are used as the main thermal insulation materials,ceramsite and sand as aggregate,plus glass fiber and sodium dodecyl sulfate to develop a new lightweight composite thermal insulation coating through orthogonal experiment *** to the plate heat flow meter method and mechanical test method,the thermal insulation and mechanical properties of EP-GHB mixed ceramsite coating were studied by making specimens with different parameter ratios,and according to the analysis of the experimental results,the optimal mix ratio of the coating was *** addition,Fluent numerical simulation software was used to establish the roadway model,and the thermal insulation effect of the coating in the roadway under different working conditions was *** results show that the thermal conductivity of the prepared composite thermal insulation coating material is only 8.5% of that of ordinary cement mortar,and the optimal thickness of adding thermal insulation coating is 0.2 m,which can reduce the outlet air temperature of the roadway with a length of 1000 m by 4.87 K at this *** thermal insulation coating developed in this study has the advantages of simple technology and strong practicability,and has certain popularization and application value in mine heat damage control.

关键词： high-temperature mine thermal insulation coating orthogonal experimental optimal fit ratio numerical simulation

Unraveling the complexity of polycystic ovary syndrome with animal models

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Journal of Genetics and Genomics 2024年第2期51卷 144-158页

作者： Huanju Liu Mixue tu Zhiyong yin Dan Zhang Jun Ma Feng He Center for Genetic Medicine The Fourth Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310058China Key Laboratory of Women's Reproductive Health of Zhejiang Province and Department of Reproductive Endocrinology Women's HospitalZhejiang University School of MedicineHangzhouZhejiang 310006China Zhejiang Provincial Clinical Research Center for Child Health Women's HospitalZhejiang University School of MedicineHangzhouZhejiang 310006China Clinical Research Center on Birth Defect Prevention and Intervention of Zhejiang Province HangzhouZhejiang 310006China Institute of Genetics Zhejiang University International School of MedicineHangzhouZhejiang 310058China Zhejiang Provincial Key Laboratory of Genetic and Developmental Disorder HangzhouZhejiang 310058China

Polycystic ovary syndrome (PCOS) is a highly familial and heritable endocrine disorder. Over half of the daughters born to women with PCOS may eventually develop their own PCOS-related symptoms. Progress in the treatment of PCOS is currently hindered by the complexity of its clinical manifestations and incomplete knowledge of its etiopathogenesis. Various animal models, including experimentally induced, naturally occurring, and spontaneously arising ones, have been established to emulate a wide range of phenotypical and pathological traits of human PCOS. These studies have led to a paradigm shift in understanding the genetic, developmental, and evolutionary origins of this disorder. Furthermore, emerging evidence suggests that animal models are useful in evaluating state-of-the-art drugs and treatments for PCOS. This review aims to provide a comprehensive summary of recent studies of PCOS in animal models, highlighting the power of these disease models in understanding the biology of PCOS and aiding high-throughput approaches.

关键词： Polycystic ovary syndrome Animal model Genetc manipulation Developmnental progtanning Drug screening