Results 41 to 50 of about 632 (122)
Research on active electrohydraulic steering control of heavy duty articulated vehicles in coal mine based on yaw motion compensation [PDF]
Due to the use of lumbar folding steering for heavy-duty articulated vehicles in coal mines, the lateral stiffness is weak and the disturbance factors are complex, making it more difficult to operate and easily causing safety problems.
Lei ZHANG +4 more
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Design of a new five-sides boring and milling head [PDF]
, 2010 在分析当前龙门式加工中心常用镗铣头优缺点基础上,提出一种新型五面复合镗铣头结构,介绍五面复合镗铣头传动结构,及其自动分度、自动装卸、自动换刀的工作原理和动作过程。A new structure of five-sides boring & milling head was presented based on analyzing advantages and disadvantages of boring & milling heads which are used usually in the ...
侯亮, 刘文志, 王浩伦
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Gaoya dianqi为提高35CrMo基活塞杆关键部位的耐磨性，防止电镀工艺带来的镀层剥落失效问题。采用激光熔覆技术在35CrMo钢基材上制备不同工艺参数的20%WC/Ni基复合涂层，利用SEM、EDS、维氏硬度计和HRS-2M往复式摩擦磨损测试仪，研究了熔覆层的宏观形貌、微观形貌、显微硬度和耐磨性，最后采用激光熔覆最优工艺参数制备活塞杆并开展10 000次机械寿命试验。激光能量密度为63.3 J/mm2能够提高熔覆层组织均匀性、降低晶粒尺寸和提高熔覆层硬度；熔覆层组织越均匀、晶粒越细小有利于硬度、摩擦磨损等性能的提高 ...
张晓敏 +8 more
doaj
Huli yanjiu, 1993 采用正确的洗脸方法是预防痤疮发生的重要手段之一.之所以这样讲,是因为洗脸不仅是洗去肌肤表面多余的皮脂,使肌肤清洁,而且还清洁了肌肤上堵塞的毛孔,使积存在角质层皮脂上的各种痤疮杆菌排出,使皮脂脱落,消除老化的角质。洗脸不仅是去掉汗和脏,更重要的是保养皮肤. 1 预防痤疮发生应注意以下几点 1.1 禁用油性化妆品; 1.2 洗脸时将头发充分地清洗; 1.3 控制糖、碳水化台·物的过量食用; 1.4 生活规律,睡眠充足; 1.5 根据季节选择洗脸皂,调节洗脸次数,夏季新陈代谢快,皮脂分泌亢进 ...
于秉丽, 张计兰, 王晓玲
doaj
Research Progress of Metal Material Liquid Forming Technology [PDF]
, 2013 随着汽车工业的迅速发展以及市场竞争对铸件质量要求的提高,推动了金属材料液态成型技术发展。从20世纪70年代压铸技术的广泛运用,到90年代挤压铸造技术的不断完善,随后挤压压铸技术不断创新,使液态成型技术向多学科渗透融合发展,应用领域不断拓展,铸件用量逐年上升。重点介绍了压铸、挤压铸造、挤压压铸这三种重要的成型技术发展以及取得的最新成果。With the rapid development of auto industry and the market competition on the increase
刘志军 +5 more
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Research on pitch control of coal mine roadheader based on fuzzy neural network PID [PDF]
Currently, PID control method is mainly used for the pitch control of coal mine roadheader, and the control precision is not high in the case of time-varying and nonlinear hydraulic system during the pitch control of roadheader.
CHAI Jianquan +5 more
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Gaoya dianqi, 2013 在高压电器产品研发过程中,利用软件建立三维虚拟数字样机,并对数字样机进行仿真分析与优化,在实体样机未制造前对结构进行运动分析,从三极联动断路器整体方案的设计、极间距的确定、传动结构的设计、操动机构的选型等几个方面进行分析研究,缩短了研发周期,节约研发成本,提高了设计质量。
马明, 刘全都, 张晓峰, 罗刚
doaj
Research on dynamic features of hydraulic system for fully mechanized mining support and its improvement design [PDF]
In the hydraulic support work of fully mechanized working face, there are often problems such as insufficient initial support force and slow moving speed of the support.
GUO Xinwei
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Gaoya dianqi, 2011 在现有配弹簧机构进行单极操作的252 kV自能式SF6断路器基础上,开发了一种配液压操动机构的三极机械联动SF6断路器,通过计算选择一种合适的液压机构及传动布置结构,使之与单极操作的断路器空载特性匹配,以达到简化试验的目的。文中重点叙述了断路器分闸过程中各相关物理量的计算公式,根据公式对三极机械联动断路器的空载特性进行编程计算,计算了几种不同液压机构的特性曲线,并将计算结果与参考机械特性曲线进行对比分析。结果表明,选取的计算结果满足简化试验的要求,为产品设计提供了理论基础。
曹云龙
doaj
Multi-objective optimization and simulation on 8-rod-mechanism working device of loaders [PDF]
, 2009 提出了一种实用性和可操作性较强的八杆机构多目标优化方法.将设计变量矩阵分解为两组耦合度较小的矩阵,提取重要度最高的几个优化目标,把其他优化目标转换成约束条件,建立起八杆机构多目标优化数学模型,同时创建了工作装置多目标优化流程.将该数学模型加载于系统动力学分析软件AdAMS,借助该软件的内建函数,把多目标优化转换成单目标优化,实现了优化过程的函数驱动与函数监测.最终实现了工作装置的快速优化与仿真.In this study,a multi-objective optimization method ...
侯亮 +4 more
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