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Electric-controlled pressure relief valve for enhanced safety in liquid-cooled lithium-ion battery packs
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作者 Yuhang Song Jidong Hou +6 位作者 Nawei Lyu Xinyuan Luo Jingxuan Ma Shuwen Chen Peihao Wu Xin Jiang Yang Jin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期98-109,I0004,共13页
The liquid-cooled battery energy sto rage system(LCBESS) has gained significant attention due to its superior thermal management capacity.However,liquid-cooled battery pack(LCBP) usually has a high sealing level above... The liquid-cooled battery energy sto rage system(LCBESS) has gained significant attention due to its superior thermal management capacity.However,liquid-cooled battery pack(LCBP) usually has a high sealing level above IP65,which can trap flammable and explosive gases from battery thermal runaway and cause explosions.This poses serious safety risks and challenges for LCBESS.In this study,we tested overcharged battery inside a commercial LCBP and found that the conventionally mechanical pressure relief valve(PRV) on the LCBP had a delayed response and low-pressure relief efficiency.A realistic 20-foot model of an energy storage cabin was constructed using the Flacs finite element simulation software.Comparative studies were conducted to evaluate the pressure relief efficiency and the influence on neighboring battery packs in case of internal explosions,considering different sizes and installation positions of the PRV.Here,a newly developed electric-controlled PRV integrated with battery fault detection is introduced,capable of starting within 50 ms of the battery safety valve opening.Furthermore,the PRV was integrated with the battery management system and changed the battery charging and discharging strategy after the PRV was opened.Experimental tests confirmed the efficacy of this method in preventing explosions.This paper addresses the safety concerns associated with LCBPs and proposes an effective solution for explosion relief. 展开更多
关键词 pressure relief valve Liquid-cooled battery pack Explosion Flacs
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Effect of Dynamic Pressure Feedback Orifice on Stability of Cartridge-Type Hydraulic Pilot-Operated Relief Valve
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作者 Yaobao Yin Dong Wang +1 位作者 Junyong Fu Hong-chao Jian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期227-241,共15页
Current research on pilot-operated relief valve stability is primarily conducted from the perspective of system dynamics or stability criteria,and most of the existing conclusions focus on the spool shape,damping hole... Current research on pilot-operated relief valve stability is primarily conducted from the perspective of system dynamics or stability criteria,and most of the existing conclusions focus on the spool shape,damping hole size,and pulsation frequency of the pump.However,the essential factors pertaining to the unstable vibration of relief valves remain ambiguous.In this study,the dynamic behavior of a pilot-operated relief valve is investigated using the frequency-domain method.The result suggests that the dynamic pressure feedback orifice is vital to the dynamic characteristics of the valve.A large orifice has a low flow resistance.In this case,the fluid in the main spring chamber flows freely,which is not conducive to the stability of the relief valve.However,a small orifice may create significant flow resistance,thus restricting fluid flow.In this case,the oil inside the main valve spring chamber is equivalent to a high-stiffness liquid spring.The main mass-spring vibration system has a natural frequency that differs significantly from the operating frequency of the relief valve,which is conducive to the stability of the relief valve.Good agreement is obtained between the theoretical analysis and experiments.The results indicate that designing a dynamic pressure feedback orifice of an appropriate size is beneficial to improving the stability of hydraulic pilot-operated relief valves.In addition,the dynamic pressure feedback orifice reduces the response speed of the relief valve.This study comprehensively considers the stability,rapidity,and immunity of relief valves and expands current investigations into the dynamic characteristics of relief valves from the perspective of classical control theory,thus revealing the importance of different parameters. 展开更多
关键词 Pilot-operated relief valve Dynamic pressure feedback orifice STABILITY RAPIDITY IMMUNITY
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Pressure relief and structure stability mechanism of hard roof for gob-side entry retaining 被引量:4
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作者 韩昌良 张农 +2 位作者 李宝玉 司光耀 郑西贵 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第11期4445-4455,共11页
In order to explore the pressure relief and structure stability mechanism of lateral cantilever structure in the stope under the direct coverage of thick hard roof and its impact on the gob-side entry retaining, a lat... In order to explore the pressure relief and structure stability mechanism of lateral cantilever structure in the stope under the direct coverage of thick hard roof and its impact on the gob-side entry retaining, a lateral cantilever fractured structural mechanical model was established on the basis of clarification for the stress environment of gob-side entry retaining, and the equation of roof given deformation and the balance judgment for fracture block were obtained. The optimal cantilever length was proposed based on the comparison of roof structural characteristics and the stress, deformation law of surrounding rocks under six different cantilever lengths by numerical simulation method. Double stress peaks exist on the sides of gob-side entry retaining and the entry located in the low stress area. The pressure of gob-side entry retaining can be relieved by reducing the cantilever length. However, due to the impact of arch structure of rock beam, unduly short cantilever would result in insufficient pressure relief and unduly long cantilever would bring larger roof stress which results in intense deformation. Therefore, there is optimal cantilever length, which was 7-8 m in this project that enables to achieve the minimum deformation and the most stabilized rock structure of entry retaining. An engineering case of gob-side entry retaining with the direct coverage of 10 m thick hard limestone roof was put forward, and the measured data verified the reasonability of conclusion. 展开更多
关键词 HARD ROOF pressure relief CANTILEVER LENGTH DOUBLE
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Pressure relief, gas drainage and deformation effects on an overlying coal seam induced by drilling an extra-thin protective coal seam 被引量:11
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作者 LIU Hai-bo CHENG Yuan-ping +2 位作者 SONG Jian-cheng SHANG Zheng-jie WANG Liang 《Mining Science and Technology》 EI CAS 2009年第6期724-729,共6页
Numerical simulations and field tests were used to investigate the changes in ground stress and deformation of, and gas flow from, a protected coal seam under which an extra-thin coal seam was drilled. The geological ... Numerical simulations and field tests were used to investigate the changes in ground stress and deformation of, and gas flow from, a protected coal seam under which an extra-thin coal seam was drilled. The geological conditions were: 0.5 meter mining height, 18.5 meter coal seam spacing and a hard limestone/fine sandstone inter-stratum. For these conditions we conclude: 1) the overlying coal-rock mass bends and sinks without the appearance of a caving zone, and 2) the protected coal seam is in the bending zone and undergoes expansion deformation in the stress-relaxed area. The deformation was 12 mm and the relative defor- mation was 0.15%. As mining proceeds, deformation in the protected layer begins as compression, then becomes a rapid expansion and, finally, reaches a stable value. A large number of bed separation crannies are created in the stress-relaxed area and the permeability coefficient of the coal seam was increased 403 fold. Grid penetration boreholes were evenly drilled toward the protected coal seam to affect pressure relief and gas drainage. This made the gas pressure decrease from 0.75 to 0.15 MPa, the gas content decrease from 13 to 4.66 m3/t and the gas drainage reach 64%. 展开更多
关键词 extra-thin protective coal seam DRILLING pressure relief expansion deformation gas drainage
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Simulating Error-Opening of Pressure Relief Valves of a Station on a Continuous Undulating Oil Pipeline with Large Elevation Difference
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作者 Xiaohua Chen Caifu Lan +3 位作者 Honghao Zheng Wang Li Chao Zhao Wenjun Dang 《Energy Engineering》 EI 2022年第4期1439-1452,共14页
For oil pipeline in mountain areas,high hydrostatic pressure in the pipeline may cause error-opening of pressure relief valves,and oil is discharged from the pipeline to the pressure relief tanks,bringing spilling-ove... For oil pipeline in mountain areas,high hydrostatic pressure in the pipeline may cause error-opening of pressure relief valves,and oil is discharged from the pipeline to the pressure relief tanks,bringing spilling-over risk of the pressure relief tanks.Therefore,simulating the error-opening situations of the pressure relief valves and investigating the oil discharge process are necessary for checking the possibility of the spilling-over accident and then proposing measures to improve the pressure relief system.This research focuses on a continuous undulating oil pipeline with large elevation difference and a station along this pipeline,which is named B station in this paper,is studied.By OLGA software,simulation model of the pressure relief system of B station is established,and the accuracy of the model is verified by reconstructing a real accident and making a comparison with the actual accident data.The maximum discharge rate reached 8284 m3/h when the pressure relief valve was opened by mistake in the inlet and outlet of the station.The accumulated filling time of the two pressure relief tanks is 200 s,which is in good agreement with the accident data.On this basis,for error-opening of the pressure relief valves at the inlet and outlet of B station,simulation is performed to investigate variations of the discharge velocity,discharge flow rate,accumulated discharge volume and ventilation volume of the vent valve.The discharge velocity is found to be over the maximum velocity allowed for safety consideration.According to the accumulated discharge volume,it is inferred that spilling over of the pressure relief tanks will be caused once error-opening of the pressure relief valve occurs.Also it is judged that the existing breathing valve can not satisfy the ventilation requirement in case of failure of the pressure relief valves.From these simulation results,it is proposed that increasing the number of vent valves,replacing the manual valves with electrically operated valves,and employing security control interlock protection program are improvement measures to guarantee safe,efficient and reliable operation of the pressure relief system at B station. 展开更多
关键词 Continuous undulating oil pipeline large elevation difference pressure relief system error-opening oil dis-charge improvement measure
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A Study on the Dynamic Adjustment of Pressure Relief Gas Drainage Drilling in Mined-Out Areas
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作者 Bo Bi Jianbing Meng Bengliang Cheng 《World Journal of Engineering and Technology》 2021年第2期337-345,共9页
With the development of coal mine equipment mechanization, the wide application of </span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">... With the development of coal mine equipment mechanization, the wide application of </span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">hole instead of roadway</span><span style="font-family:Verdana;">”</span><span style="font-family:Verdana;"> technology greatly reduces the cost of gas control engineering, but puts forward higher requirements for the effect of gas drainage. At present, the drainage effect of coal mine inspection boreholes is mainly evaluated by the drilling field, but the flow rate and gas concentration of each borehole in the drilling field are not the same, which causes the gas drainage effect not to be correctly mastered. In the present study, the pressure relief drilling in the goaf of the working face of a typical multi-coal seam group high gas outburst mining area was taken as the research object. Through the newly developed portable drilling inspection device, the pure amount of drilling drainage was investigated, and the drilling design was dynamically adjusted. The enhancement of the goaf pressure relief gas control effect ensures the gas safety of the mining face. At the same time, this improves the gas extraction rate and reduces the emission of greenhouse gases. If the data from the borehole investigation can be transmitted in real time and analyzed in big data, the optimal extraction negative pressure can be predicted through a regression algorithm. Under the control of the negative pressure of each borehole by the actuator, the extraction system can have the function of intelligent judgment. 展开更多
关键词 pressure-relief Gas Extraction Study on the Extraction Effect Borehole Design Determination of Pore Parameters
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Mechanical analysis of effective pressure relief protection range of upper protective seam mining 被引量:10
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作者 Yin Wei Miao Xiexing +1 位作者 Zhang Jixiong Zhong Sijian 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第3期537-543,共7页
This paper analyzes the control mechanism of coal and gas outbursts and proposes the concept of an effective pressure relief protection range, based on the stress relief of the underlying coal-rock mass and the develo... This paper analyzes the control mechanism of coal and gas outbursts and proposes the concept of an effective pressure relief protection range, based on the stress relief of the underlying coal-rock mass and the development of a plastic zone. Also this study developed a stress change and fracture development model of the underlying coal-rock mass. In addition, the stress and depth of fracture of any point in the floor were deduced with the application of Maple Calculation Software. The specific engineering parameters of the Pingdingshan No. 12 colliery were applied to determine the relationship between the depth of fracture in the floor and the mining height. The pressure-relief principle of the underlying coal-rock mass was analyzed while varying the mining height of the upper protective seam. The findings indicate that as the depth of fracture in the floor increases, the underlying coal-rock mass experiences a limited amount of pressure relief, and the pressure relief protection range becomes narrower.Additionally, the stress distribution evolves from a ‘‘U" shape into a ‘‘V" shape. A 2.0 m mining height of protective seam situates the outburst-prone seam, Ji_(15), within the effective pressure relief protection range. The fracture development and stress-relief ratio rises to 88%, ensuring the pressure-relief effect as well as economic benefits. The measurement data show that: after mining the upper protective seam, the gas pressure of Ji_(15) dropped from 1.78 to 0.35 MPa, demonstrating agreement between the engineering application and the theoretical calculation. 展开更多
关键词 Upper protective seam Principle of pressure relief Effective protection range Gas pressure
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Optimum location of surface wells for remote pressure relief coalbed methane drainage in mining areas 被引量:9
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作者 HUANG, Huazhou SANG, Shuxun +3 位作者 FANG, Liangcai LI, Guojun XU, Hongjie REN, Bo 《Mining Science and Technology》 EI CAS 2010年第2期230-237,共8页
Based on engineering tests in the Huainan coal mining area,we studied alternative well location to improve the performance of surface wells for remote pressure relief of coalbed methane in mining areas.The key factors... Based on engineering tests in the Huainan coal mining area,we studied alternative well location to improve the performance of surface wells for remote pressure relief of coalbed methane in mining areas.The key factors,affecting location and well gas production were analyzed by simulation tests for similar material.The exploitation results indicate that wells located in various positions on panels could achieve relatively better gas production in regions with thin Cenozoic layers,low mining heights and slow rate of longwall advancement,but their periods of gas production lasted less than 230 days,as opposed to wells in regions with thick Cenozoic layers,greater mining heights and fast rates of longwall advancement.Wells near panel margins achieved relatively better gas production and lasted longer than centerline wells.The rules of development of mining fractures in strata over panels control gas production of surface wells.Mining fractures located in areas determined by lines of compaction and the effect of mining are well developed and can be maintained for long periods of time.Placing the well at the end of panels and on the updip return airway side of panels,determined by lines of compaction and the effect of mining,would result in surface wells for remote pressure relief CBM obtaining their longest gas production periods and highest cumulative gas production. 展开更多
关键词 pressure relief coalbed methane surface wells well location Huainan coal mining area
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Principle and engineering application of pressure relief gas drainage in low permeability outburst coal seam 被引量:15
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作者 LIU lin CHENG Yuan-ping +2 位作者 WANG Hai-feng WANG Liang MA Xian-qin 《Mining Science and Technology》 EI CAS 2009年第3期342-345,351,共5页
With the increase in mining depth, the danger of coal and gas outbursts increases.In order to drain coal gas effectively and to eliminate the risk of coal and gas outbursts, we used a specific number of penetration bo... With the increase in mining depth, the danger of coal and gas outbursts increases.In order to drain coal gas effectively and to eliminate the risk of coal and gas outbursts, we used a specific number of penetration boreholes for draining of pressure relief gas.Based on the principle of overlying strata movement, deformation and pressure relief, a good effect of gas drainage was obtained.The practice in the Panyi coal mine has shown that, after mining the C11coal seam as the protective layer, the relative expansion deformation value of the protected layer C13 reached 2.63%, The permeability coefficient increased 2880 times, the gas drainage rate of the C13 coal seam increased to more than 60%, the amount of gas was reduced from 13.0 to 5.2 m3/t and the gas pressure declined from 4.4 to 0.4 MPa, which caused the danger the outbursts in the coal seams to be eliminated.The result was that we achieved a safe and highly efficient mining operation of the C13 coal seam. 展开更多
关键词 protective layer mining technology principle drainage of pressure relief gas engineering application
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Exploitation technology of pressure relief coalbed methane in vertical surface wells in the Huainan coal mining area 被引量:13
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作者 HAN Jia-zhang SANG Shu-xun +1 位作者 CHENG Zhi-zhong HUANG Hua-zhou 《Mining Science and Technology》 EI CAS 2009年第1期25-30,共6页
Exploitation technology of pressure relief coalbed methane in vertical surface wells is a new method for exploration of gas and coalbed methane exploitation in mining areas with high concentrations of gas, where tecto... Exploitation technology of pressure relief coalbed methane in vertical surface wells is a new method for exploration of gas and coalbed methane exploitation in mining areas with high concentrations of gas, where tectonic coal developed. Studies on vertical surface well technology in the Huainan Coal Mining area play a role in demonstration in the use of clean, new energy resources, preventing and reducing coal mine gas accidents and protecting the environment. Based on the practice of gas drainage engineering of pressure relief coalbed methane in vertical surface wells and combined with relative geological and exploration en- gineering theories, the design principles of design and structure of wells of pressure relief coalbed methane in vertical surface wells are studied. The effects of extraction and their causes are discussed and the impact of geological conditions on gas production of the vertical surface wells are analyzed. The results indicate that in mining areas with high concentrations of gas, where tectonic coal developed, a success rate of pressure relief coalbed methane in surface vertical well is high and single well production usually great. But deformation due to coal exploitation could damage boreholes and cause breaks in the connection between aquifers and bore-holes, which could induce a decrease, even a complete halt in gas production of a single well. The design of well site location and wellbore configuration are the key for technology. The development of the geological conditions for coalbed methane have a significant effect on gas production of coalbed methane wells. 展开更多
关键词 pressure relief coalbed methane EXPLOITATION vertical surface well Huainan coal mining area
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Pressure Control of a Large-scale Hydraulic Power Unit Using π Bridge Network 被引量:3
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作者 FENG Bin GONG Guofang YANG Huayong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第3期386-391,共6页
The steady state and dynamic characteristics of pressure output of a hydraulic power unit are important to the hydraulic system behavior.Because of the compact structure,the B-half bridge resistance network is widely ... The steady state and dynamic characteristics of pressure output of a hydraulic power unit are important to the hydraulic system behavior.Because of the compact structure,the B-half bridge resistance network is widely used in the pilot controlled pressure relief valves.However the steady-state pressure error might be unacceptably big in those pressure control systems.A constant pressure power unit is typically assumed in analysis of steady state and dynamic behavior of hydraulic systems.The flow-pressure relationship seems to be much complex,in particular when big flow variation takes place.In this paper,the π bridge hydraulic resistance network pilot stage is designed in order to get better flow-pressure characteristics.Based on the similarity of electrical circuits,the main factors influencing flow-pressure characteristics are analyzed.Moreover,the optimum diameters of both constant hydraulic resistor and dynamic resistor are proposed.Flow-pressure characteristics are compared with different constant hydraulic resistors,dynamic resistor and spring stiffness by simulations and experiments.Results of simulations and experiments show that flow-pressure characteristics depend very little on the spring stiffness in whole flow range.Good controlled pressure characteristics can be achieved with suitable constant resistors.Overshoot can be reduced with the small diameter of the dynamic resistor.Flow-pressure characteristics of pressure relief valve can be improved with a π bridge pilot stage.The proposed pressure control method will provide some positive guidelines and be helpful to design a high performance hydraulic system with large flow. 展开更多
关键词 two stage pressure relief valve π bridge resistor network flow-pressure characteristics
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沿空留巷“内支-外卸”围岩控制技术研究与应用 被引量:1
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作者 李明 《煤炭工程》 北大核心 2024年第3期102-109,共8页
为解决现场实际中沿空留巷受采动影响围岩变形破环严重问题,以山西晋城东峰矿为工程背景,分析了沿空留巷不同阶段覆岩运移规律,明确了围岩控制的重点。确定了采用“内支-外卸”的协同控制方式,采用理论分析、现场应用与监测的手段着重... 为解决现场实际中沿空留巷受采动影响围岩变形破环严重问题,以山西晋城东峰矿为工程背景,分析了沿空留巷不同阶段覆岩运移规律,明确了围岩控制的重点。确定了采用“内支-外卸”的协同控制方式,采用理论分析、现场应用与监测的手段着重对巷旁柔模混凝土支护与顶板超前爆破预裂卸压进行了设计、分析与效果检验。研究结果表明,沿空留巷巷道在滞后工作面100 m范围内巷道变形速度较大,柔模墙体在滞后工作面200 m范围内压力变化较大并达到最高值,应为维护重点;现场优化后的巷旁支护体能够满足巷帮的承载能力;柔模混凝土墙巷旁支护和超前爆破预裂切顶卸压协同发挥作用,在降低采动应力影响、改善留巷应力环境的同时提高了巷帮的支护强度,有效地提高了留巷围岩的稳定性。 展开更多
关键词 沿空留巷 覆岩运动 爆破预裂卸压 柔模混凝土
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Pore-scale study of the pressure-sensitive effect of sandstone and its influence on multiphase flows 被引量:4
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作者 Jun-Jian Li Yang Liu +2 位作者 Ya-Jun Gao Bao-Yang Cheng Han-Qiao Jiang 《Petroleum Science》 SCIE CAS CSCD 2019年第2期382-395,共14页
The pressure-sensitive effect on the pore structure of sandstone was investigated using X-ray computed micro-tomography and QEMSCAN quantitative mineral analysis. In a physical simulation study, we extracted the pore ... The pressure-sensitive effect on the pore structure of sandstone was investigated using X-ray computed micro-tomography and QEMSCAN quantitative mineral analysis. In a physical simulation study, we extracted the pore network model from digital cores at different confining pressures and evaluated the effect of pressure sensitivity on the multiphase displacement process. In both the pore network model and QEMSCAN scanning, the pore structure was observed to be damaged under a high confining pressure. Due to their different scales, the pores and throats exhibited inhomogeneous changes; further, the throats exhibited a significant variation compared to that exhibited by the pores. Meanwhile, the heterogeneity of the pore structure under the two aforementioned activities was aggravated by the elastic-plastic deformation of the pore structure.The pressure-sensitive effect increased the proportion of mineral particles, such as quartz(the main component of the core skeleton), and reduced the proportion of clay minerals. The clay minerals were originally attached to the pore walls or interspersed in the pores; however, as the pressure increased, the clay minerals accumulated in the pores resulting in blockage of the pores. While simulating the multiphase displacement process, increasing the confining pressure was observed to severely restrict the flowability of oil and water. This study promises to improve the efficiency of reservoir development in terms of oil and gas exploitation. 展开更多
关键词 pressure SENSITIVE - QEMSCAN MICRO-CT PORE network model MULTIPHASE flow
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基于Relief-PGS优化算法的数据分类
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作者 张菡玫 《河南科技》 2023年第24期31-35,共5页
【目的】在选取图像特征对图像进行分类时,选取的特征属性是否冗余会影响到图像分类的正确率。为提高分类的准确率,使用Relief-PGS优化算法对特征子集和支持向量机参数同步进行优化。【方法】首先使用Relief算法对特征数据集进行筛选,... 【目的】在选取图像特征对图像进行分类时,选取的特征属性是否冗余会影响到图像分类的正确率。为提高分类的准确率,使用Relief-PGS优化算法对特征子集和支持向量机参数同步进行优化。【方法】首先使用Relief算法对特征数据集进行筛选,其次将筛选出的特征子集数目和支持向量机参数一起编码到粒子群-遗传算法中进行同步优化,最后对处理后的数据集进行分类,能有效提高分类的准确率。【结果】选取UCI数据库中的5种数据集进行分类,与传统的SVM算法、PGS算法和Relief-SVM算法相比,Relief-PGS优化算法对图像分类的准确率分别提高了22.53%、6.05%和11.16%。【结论】研究结果表明,Relief-PGS算法在去掉不重要特征的同时,对支持向量机参数进行优化,能有效提高分类的准确率。 展开更多
关键词 特征选择 relief算法 遗传-粒子群算法 支持向量机
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“砼墙-切顶-让压”沿空留巷技术分析及应用 被引量:2
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作者 吴玉意 曹晓凡 +5 位作者 刘成勇 秋丰岐 刘武强 赵萌烨 王翰秋 刘保贵 《煤炭技术》 CAS 2024年第1期85-89,共5页
采用理论分析,建立相应的沿空留巷巷旁支护力学模型,提出采用“砼墙-切顶-让压”沿空留巷技术,并以新集一矿360804综采工作面运输巷沿空留巷为背景,并进行工程实践和现场实测。结果表明:坚硬顶板、深部复杂矿井采用“柔模-切顶”沿空留... 采用理论分析,建立相应的沿空留巷巷旁支护力学模型,提出采用“砼墙-切顶-让压”沿空留巷技术,并以新集一矿360804综采工作面运输巷沿空留巷为背景,并进行工程实践和现场实测。结果表明:坚硬顶板、深部复杂矿井采用“柔模-切顶”沿空留巷仍然极有可能出现应力集中从而破坏柔模墙体的现象;“砼墙-切顶-让压”沿空留巷技术可以缓解顶板压力,防止墙体受压破坏,充分发挥围岩的自稳性能;新集一矿沿空留巷最大顶底板移近量为361 mm,最大两帮移近量为189 mm,巷道变形在允许范围内,留巷效果较好。该研究可以为相似工程提供借鉴。 展开更多
关键词 深部矿井 沿空留巷 柔模混凝土 切顶卸压
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复合磁-电弹簧直动式溢流阀设计与性能分析
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作者 刘振阳 吴张永 +4 位作者 蒋佳骏 朱启晨 谢志伟 王东圣 杨瑜君 《机床与液压》 北大核心 2024年第8期39-45,共7页
为了解决传统机械弹簧因塑性变形、断裂等造成溢流阀工作性能劣化的问题,设计一种复合磁-电弹簧结构应用于直动式溢流阀调压弹簧中,以提高直动式溢流阀的响应速度,实现电控弹簧力。理论分析复合磁-电弹簧磁力特性,利用Maxwell软件对复合... 为了解决传统机械弹簧因塑性变形、断裂等造成溢流阀工作性能劣化的问题,设计一种复合磁-电弹簧结构应用于直动式溢流阀调压弹簧中,以提高直动式溢流阀的响应速度,实现电控弹簧力。理论分析复合磁-电弹簧磁力特性,利用Maxwell软件对复合磁-电弹簧进行磁力特性仿真;采用AMESim软件对机械弹簧直动式溢流阀和复合磁-电弹簧直动式溢流阀进行动态特性仿真。对复合磁-电弹簧磁力特性及溢流阀的动态特性进行实验测试。结果表明:复合磁-电弹簧设计合理,复合磁-电弹簧直动式溢流阀动态响应特性优于现有机械弹簧直动式溢流阀。 展开更多
关键词 溢流阀 调压弹簧 磁弹簧 磁力特性 动态响应特性
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Pressure relief of underground ammunition storage under missile accidental ignition
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作者 Ya-wei Wang Yu-zhuo Yang +2 位作者 Gao-wan Zou Hui Dong Yan Huo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第3期1081-1093,共13页
Safety of underground ammunition storage is an important issue,especially during the accidental ignition of missiles.This work investigates the pressure and temperature distribution of the multi-layer underground ammu... Safety of underground ammunition storage is an important issue,especially during the accidental ignition of missiles.This work investigates the pressure and temperature distribution of the multi-layer underground ammunition storage with a pressure relief duct during the accidental ignition process of the missile.A large-scale experiment was carried out using a multi-layered restricted space with a pressure relief duct to simulate the underground ammunition store and a solid rocket motor to simulate the accidental ignition of the missile.The results show that when the motor gas mass flow increased by5.6 times,the maximum pressure of the ammunition storage increased by 5.87 times.At a certain motor flow rate,when the pressure relief exhaust area at the end of the relief duct was reduced by 1/2,the maximum pressure on the first layer did not change.But the rate of pressure relief was reduced and the time delayed for the pressure of ammunition store to drop to zero.In this experiment,when the motor ignition position was located in to the third layer ammunition chamber,the maximum pressure was reduced by 32.9%and also reduced the rate of change of pressure.In addition,for the experimental conditions,the theoretical analysis of the pressure relief of the ammunition storage is given by a simplified model.Based on the findings,some suggestions to the safety protection design of ammunition store are proposed. 展开更多
关键词 Underground ammunition storage pressure relief Large-scale experiment Missile accidental ignition
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An analysis on the effect of mining height and floor lithology on pressure relief of upper protective layers
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作者 Xu-chao HUANG Dong-ling SUN Kang-wu FENG 《Journal of Coal Science & Engineering(China)》 2013年第1期46-50,共5页
In order to understand the effect of mining height and floor lithology at the upper protective layer face on the pressure relief of protected coal seams, this paper uses a numerical simulation method to model the pres... In order to understand the effect of mining height and floor lithology at the upper protective layer face on the pressure relief of protected coal seams, this paper uses a numerical simulation method to model the pressure changes at protected coal seam during mining upper protective layer. The results show that the taller the mining height at the upper protective layer face, the greater the protection on protected coal seam due to the higher level of pressure release; the upper protective layer face with hard rock floor impedes the pressure release at the protected coal seam, which affects the overall effect of the pressure release at protected coal seam using the protective layer mining method. 展开更多
关键词 mining height floor lithology mining upper protective layer pressure relief EFFECT
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沿空留巷围岩控制技术在2-300采面的应用 被引量:1
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作者 马君蒲 《江西煤炭科技》 2024年第2期78-80,84,共4页
干河煤矿2-300工作面开采厚煤层,采用110工法。为控制工作面沿空留巷的围岩变形,设计了“切顶卸压+恒阻锚索”围岩控制方案,配合使用“金属网+钢筋网+可伸缩U型钢”联合挡杆技术隔绝采空区。应用结果表明,留巷巷道回采期间顶底板移近量... 干河煤矿2-300工作面开采厚煤层,采用110工法。为控制工作面沿空留巷的围岩变形,设计了“切顶卸压+恒阻锚索”围岩控制方案,配合使用“金属网+钢筋网+可伸缩U型钢”联合挡杆技术隔绝采空区。应用结果表明,留巷巷道回采期间顶底板移近量最大为76mm,巷帮变形量最大为49mm,围岩变形均在可控范围内。 展开更多
关键词 沿空留巷 围岩控制 切顶卸压 联合挡杆技术
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松软煤层大巷群卸-注-锚协同防控围岩变形技术研究
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作者 范恺 《矿业安全与环保》 CAS 北大核心 2024年第5期76-82,共7页
为防控松软煤层大巷群在非对称应力作用下发生流变变形,以赵庄煤业三盘区大巷群受采动影响产生持续性变形为研究背景,提出了卸-注-锚协同防控围岩变形新技术。通过开展数值模拟和宽煤柱护巷顶板结构分析,阐明了大巷群应力状态与采空区... 为防控松软煤层大巷群在非对称应力作用下发生流变变形,以赵庄煤业三盘区大巷群受采动影响产生持续性变形为研究背景,提出了卸-注-锚协同防控围岩变形新技术。通过开展数值模拟和宽煤柱护巷顶板结构分析,阐明了大巷群应力状态与采空区顶板的关联性,揭示了爆破裂隙带在阻隔应力传递的作用机制,明确了回采巷道顶板爆破预裂和盘区大巷多层位预裂的理论依据,构建了深-浅孔联合卸压工艺和以锚固-注浆为核心的内外圈协同加固技术,根据理论推演和现场试验确定了爆破预裂参数和注浆参数。工程实践表明:爆破工艺实现了坚硬顶板的充分预裂,锚固-注浆工艺提升了巷道围岩的整体性,3312工作面回采后大巷群顶底板和两帮移近量较小,达到了卸-注-锚协同防控围岩变形的目的。 展开更多
关键词 煤层大巷群 顶板预裂 注浆加固 卸压 围岩变形
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