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洛阳装备制造业具有雄厚的工业基础和显著的科技优势,但发展中存在企业自主创新能力较差、产品结构不够合理等问题,为此,本文提出应通过加大政策支持力度、深化科技体制改革等途径促进洛阳装备制造业发展。 相似文献
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The continuous heating transformation program is developed to investigate the influence of continuous annealing technological
parameters on recrystalization for cold-rolled strip in galvanizing line. This program can be used for the calculation of
the continuous annealing temperature field of strip steel, determination of the start and end time of recrystallization in
continuous heating process, and procurement of the continuous heating transformation diagram. The temperature field for continuous
annealing is simulated by means of finite difference method. Based on the Scheil superposition principle, the continuous heating
transformation curve is obtained by using time temperature transformation (TTT) curve which is measured experimentally. The
developed program has been used in practice, and the strip speed on production line increases by more than 10%. 相似文献
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Warm surface rolling is a working process between room temperature and re-crystallization temperature. With warm surface rolling of steel grade 45 grooved axle, its fatigue lifespan was measured by the endurance bending test. The influence of surface rolling reduction on the axle fatigue life period was experimentally studied at different surface rolling temperatures. The experimental results show that the fatigue life of the steel axles can be significantly improved by the warm surface rolling process. The optimum rolling reductions for the maximum fatigue life at different warm surface rolling temperatures were explored. The microstructures of the steel axles were analyzed. The surface strength improved by refining grains after the warm surface rolling was calculated by the Hall-Petch model. These research achievements could be also valuable to the relevant works. 相似文献
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The numerical thermal mechanical simulation of radial forging process of steel H13 stepped shaft with GFM (Gesellschaft fur Fertigungstechnik und Maschinenbau) forging machine was carried out by three-dimensional finite element code DEFORM 3D. According to the effective plastic strain, the mean stress and the mean plastic strain distribution of the radial forging, the forging penetration efficiency (FPE) was studied throughout each operation. The results show that the effective plastic strain in the center of the forging is always greater than zero for the desirable larger axial drawing velocity. The mean stress in the center of the workpiece is proposed to describe hydrostatic pressure in this paper. There is compressive strain layer beneath the surface of the workpiece to be found, while there is tensile strain core in the center of the workpiece. These results could be a valuable reference for designing the similar forging operations. 相似文献
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在高校专业课中开展双语教学,是高等教育教学改革的有益尝试。本文在分析高校专业课双语教学必要性的基础上,提出从选择合适的学生班级、教材、教学内容、教学方式、方法和培训双语师资六个方面来加强高校专业课双语教学。 相似文献
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我国“一带一路”战略的实施,给洛阳带来了前所未有的发展机遇,同时也为银行卡业务发展提供了广阔的空间.本文研究了洛阳银行银行卡营销策略,在对洛阳银行银行卡业务进行SWOT分析基础上,结合洛阳经济环境及洛阳市银行卡市场波特五种竞争力分析,从产品、价格、渠道、促销四个方面探讨了洛阳银行银行卡营销策略. 相似文献
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悬索桥主塔上横梁施工是典型的高空作业,施工难度大、安全风险高,合理地进行支架设计是质量安全的保障。介绍了虎门二桥大沙水道桥东西塔上横梁采用的两种支架搭设方式,并创新地采用反拉法进行支架预压,在经济性、安全性等方面比较各自的优势。 相似文献