矿用干式变压器故障诊断和寿命预测技术现状及展望

干式变压器故障诊断技术通过对监测数据进行分析,能够实现信号特征提取、故障诊断、状态评估和寿命预测,提高干式变压器在井下运行的安全性,降低由于故障带来的损失。文章介绍了信号特征提取方法(频率响应法、小波变换法、堆叠自编码器)、故障诊断方法(贝叶斯网络、支持向量机、BP神经网络)、状态评估和寿命预测方法(交叉熵组合预测法、灰色理论、层次分析法)的研究现状,将几种方法进行对比,并对干式变压器故障诊断技术进行展望。     

聚合氯化铝盐基度对残余铝的影响分析

采用Ferron逐时络合比色法,分析了不同盐基度的PAC中Ala、Alb、Alc的分布。结果表明:随着盐基度的增加,Ala含量显著下降,总溶解性残余铝与混凝过程中Ala的含量直接相关。p H对聚合铝的形态分布影响很大,尤其是Ala。盐基度越高,PAC对pH值的适应范围越宽。在0～91%内,随着盐基度的增大,混凝效果提高,沉后水残余铝降低,但盐基度在85%以上时变幅趋缓。     

国内新建锌冶炼厂工艺应用现状

广泛收集整理国内有关锌冶炼厂工艺现状的基础上,对锌冶炼的工艺发展过程、工艺流程、工艺特点及应用进行阐述。工艺应用显示:由于国家环保要求及加强供给侧结构性改革和扩大市场需求,现阶段国内大多数冶炼厂都采用了部分湿法冶炼工艺或全湿法冶炼工艺,湿法冶炼将成为锌冶炼的主要发展方向,而锌精矿直接氧压浸出将成为主流工艺。     

刘宝万艺术作品欣赏

刘宝万在数十年艺术积淀的基础上,别出心裁,利用各种布头贴画,依托淄博的地域文化,如蹴鞠、聊斋故事、历史人物、抗日战争等题材及博山民间传统艺术制作的布头画,构思精巧,立体感强,色彩鲜活,栩栩如生。经山东电视台报道后,相继被央视和北京、上海、天津、浙江、黑龙江及香港、澳门、台湾等三十余家卫视转播,人民网、百度网等各大网站,将其称为"巧手哥"。     

PC—01水泥聚苯保温板

介绍了用废聚苯乙烯泡沫塑料粒与水泥、胶粘剂等组分混合制成的水泥聚苯保温板的生产工艺、产品性能及施工方法。     

不同气候条件下典型城市的体育馆 自然通风模拟及潜力分析

对夏热冬暖与温和气候条件下的典型城市体育馆进行了自然通风数值模拟及潜力分析。首先,对两种气候条件中的典型城市体育馆进行了自然通风数值模拟;然后,通过对比不同地区典型城市夏季、冬季和过渡季节的气流组织和舒适性分布情况,提出了合理的风压驱动自然风设计策略;最后,对不同气候条件中典型性城市的体育馆自然通风进行了潜力分析。     

Evaluation method for expressway rock slope stability based on numerical simulation

Taking the deep cutting excavation of Beijing-Qinhuangdao expressway as an example, the paper utilizes DYNA-2D dynamic FEM procedure to simulate the rock blasting process. The computation model was based on dynamical response of nonlinear elasto-plasticity material. According to analyses of the distribution and transmission of stress field, displacement field, velocity field, and acceleration in the course of blasting,and discusses of the blasting vibration influence to the rocky cut slope from many sides.the calculated results met well with that of in situ measured results. It is easy to determine vibration state of any point in the slope such as stress, displacement, velocity and acceleration, which confirm that numerical simulation method is feasible. The meaning of this research is not only to design the blasting construction to forecast and prevent the expressway rocky slope from disaster in mountains area, but also to offer a new experience of numerical method in geotechnical field.     

Stability analysis of the open-pit mine slope and the study on the incensement of the slope angle

Based on the exploration of the engineering geology and the rock mechanics testing, limit equilibrium analysis method was adopted to calculate the stability of the Huogeqi Copper Mine slope, the results show that the original slope angle is too conservative and the slope have the potential of more preferable slope angle. In order to discuss the possibility of slope angle enhancement, sensitivity analysis of parameters related to limit state slope was made. Quantitatively determined angle value of the adding and the optimal slope angle was obtained. The study having performed showed that it is not only useful for the safety control of open-pit mine slope but also for the open-pit mine design for the similar geological condition.     

紧邻既有线路基深基坑支护结构变形影响因素分析

为系统分析紧邻既有线路基桥梁基础深基坑支护结构的受力变形特性及其主要影响因素,结合某高速公路桥梁基础基坑工程,利用MIDAS/GTS软件进行平面数值计算,深入探讨了不同开挖深度、不同相隔间距、不同基坑尺寸、不同嵌固深度、不同桩基刚度等对支挡结构变形特征的影响,为既有路基旁基坑开挖支护设计提供了技术参考。     

正铲液压挖掘机工作装置的动力学分析与仿真

对一种正铲液压挖掘机进行动力学分析,运用虚功原理对工作装置进行动力学建模。基于Matlab对动力学模型进行数值计算,在给定负载情况下得到了铲斗在挖掘过程中3组液压缸的驱动力变化曲线。利用ADAMS仿真软件对该挖掘机工作装置进行动力学仿真,将仿真得到的结果与计算值进行对比,得到3组液压缸的驱动力误差曲线,误差在合理范围内,证明了动力学建模方法的正确性。