第五阶段和第六阶段排放标准对比研究

目前,机动车污染物排放已成为一个全球性问题,而在实验室达标的机动车或发动机,在实际使用过程中排放可能会大幅升高。面对这一情况,我国法规对发动机排放要求越来越高。文章通过对第五阶段和第六阶段PEMS试验方法对比,总结不同阶段车辆排放的要求。     

Research on confirmation of basic technological parameters of tension levellers based on neural network and genetic algorithm

Confirmation of basic technological parameters of tension levellers is the most important factor of leveling strip. Up to now, most factories have used experts' experience to decide these parameters, without any established rule to follow. For better quality of strip, a valid method is needed to decide technological parameters precisely and reasonably. In this paper, a method is used based on neural network and genetic algorithm. Neural network has a good ability to extract rules from work process of tension levellers. Then using neural network, which has learned from a lot of working samples, to be the evaluation of fitness, genetic algorithm could easily find the best or better technological parameters. At the end of this paper, examinations are given to show the effect of this method.     

基于视频图像处理的舰船运行状态监测技术

传统的舰船运行状态监测技术响应时间长,不能实现实时监测,监测效果差。为了解决上述问题,研究一种新的舰船运行状态监测技术,引入视频图像处理技术,首先对舰船运行状态信息进行采集,然后通过提取的视频图像特征处理舰船运行状态信息,最后输出舰船运行状态信息结果。为检测该技术工作效果,与传统监测技术进行对比,结果表明,研究的监测技术响应时间短,效果好,具有广阔的市场应用空间。     

职业本科新能源汽车工程技术专业智能网联汽车实训室建设初探

为进一步完善教学体系,发展本科层次的职业教育,院校应把职业教育作为类型教育的重要举措。职业本科新能源汽车工程技术专业建设,除了理论专业的教学外,更加注重的是职业技能培养。学生培养主要依托新能源汽车实训基地,特别是智能网联汽车实训室建设,为培养学生的实践操作能力,提升学生的核心竞争力提供硬件保障。文章对职业本科新能源汽车工程技术专业智能网联汽车实训室建设进行初步探索,给出了高水平实训基地建设方案,为职业本科院校在新形势下建设高水平实训基地提供一定参考。     

27.5kV所用干式变压器谐波铜耗仿真研究

近年来,铁路系统所用干式变压器运行过程中出现绝缘、绕组烧毁等现象,为了分析该现象发生的原因,分析了电力机车向牵引网系统注入的高次谐波对所用干式变压器铜耗的影响.考虑谐波情况下绕组集肤效应及邻近效应引起的损耗,基于场路耦合法,建立所用干式变压器的详细三维有限元模型;分别将单次谐波电流与复合次谐波电流作用下的所用干式变压器...     

黄淮冲积平原地区高速铁路螺杆桩复合地基应用研究

依托郑徐客运专线兰考南站路基工程螺杆桩复合地基项目,通过试桩和桩身质量检测,总结黄淮冲积平原地区螺杆桩关键施工工艺和质量控制措施,同时对螺杆桩承载力特性及复合地基进行工后沉降分析。结果表明：黄淮冲积平原地区粉质黏土、粉砂、细砂、圆砾土土层中可以形成螺杆桩螺纹段桩身,成桩质量良好;螺杆桩单桩承载力和复合地基承载力满足设计要求;该地区同等条件下,螺杆桩极限承载力较普通灌注桩提高约24%;复合地基沉降主要发生在填筑期;双曲线法预测得出三个观测断面工后沉降量均小于15 mm,满足无砟轨道铺设要求。     

基于熵权法和可拓学理论的隧道围岩质量评价

引入可拓学理论,建立隧道围岩质量评价物元模型,采用熵权法计算指标权重,选取岩石单轴饱和抗压强度RC、围岩质量指标RQD值、结构面摩擦系数Jf、节理间距Jd、地下水状态W、完整性系数Kv为评价指标,对坪子头隧道左线围岩质量等级进行评价,研究表明,基于熵权法的围岩质量可拓评价不仅取得了与工程地质报告相一致的评价结果,而且能客观反映待评围岩与相邻围岩等级之间的距离,从而提供更为准确的围岩级别,为隧道施工提供了科学依据。     

Research of the image processing in dynamic flatness detection based on improved laser triangular method

As a commonly used non-contact flatness detection method, laser triangular detection method is designed with low cost, but it cannot avoid measurement errors caused by strip steel vibration effectively. This paper puts forward a dynamic flatness image processing method based on improved laser triangular detection method. According to the practical application of strip steel straightening, it completes the image pre-processing, image feature curve extraction and calculation of flatness elongation using digital image processing technology. Finally it eliminates elongation measurement errors caused by the vibration.