瓷支柱绝缘子偏心程度对力学性能影响研究

瓷支柱绝缘子作为电力设备绝缘条件下的关键支撑结构,其力学性能决定了相关设备的承载能力,而瓷柱偏心程度影响绝缘子力学性能。针对不同偏心程度的瓷支柱绝缘子建立了有限元数值模型并进行了数值计算分析,结果表明瓷支柱绝缘子的偏心程度越高时其承载强度越低。计算结果验证了通过数值仿真手段研究绝缘子力学性能的可行性,可为瓷绝缘子的设计制造提供理论指导和技术支持。     

横置双离合器自动变速器速比设定方法

横置双离合器自动变速器传动系统结构复杂,仅根据理论方法设定的速比无法快速实现齿轮参数选配及设计。本文根据双离合器自动变速器传动系统特点,分析其结构、齿轮啮合关系、轴心距等设置对速比的影响,提出一种既遵循理论速比设定的要求,又满足变速器实际结构等因素限制的速比设定方法。实际应用结果表明该速比设定方法可行,能够实现横置双离合器自动变速器复杂结构状态下的实际速比设定,且匹配车辆能够满足整车动力性及经济性相关目标要求。     

大功率IGBT电源中频电炉的调试

介绍了大功率IGBT电源中频电炉调试中遇到的问题,对于IGBT模块烧损现象,通过将Q2和Q4两组IGBT模块导通,在固定时间内使再生回流电流形成一个内循环,避免再生电流对中间电容充电造成电压上升过高;对于电控柜异常发热现象,通过选择规格为1 400 V的二极管,在二极管处并联一个电容,并增设一个报警检测系统,使该问题得以解决;对于炉衬使用寿命短的问题,通过对水泥线圈外层及裂纹进行清理,并用水泥对裂纹进行密封,规范云母片的铺设规范,要求接头处搭接至少60 mm,层与层的接缝要错开,以最大限度阻隔C、Zn等向水泥层渗透,并优化炉衬烧结工艺,调整增加渗C剂的时机,最终使平均炉衬寿命达到120~140炉次。     

车载导航系统中GPS数据的采集与处理

针对我国交通拥堵所带来的问题,本文以城市出租车为载体,从智能交通的GPS数据采集入手,以Delphi为开发工具,对浮动车采集的数据进行研究。同时,采用第三方支持多线程工作的串口通信控件Spcomm,实现串口通信和GPS数据的采集。研究结果表明,通过GPS信息可以在任意时间获取任何地点的位置信息,并能获得相应载体的速度和方向等信息,该方法实现了GPS数据的接收、存储、转换和文本写入,同时该方法也可对工业数据采集、路灯、水电气实时监控,具有一定的实际应用前景。     

粉煤灰吸附剂的最新研究进展

概述了近几年国内外粉煤灰吸附剂研究情况,讨论了粉煤灰吸附剂在去除水体中氮、磷、重金属离子,净化烟气中SO2、NOx、Hg等有毒有害污染物的应用,此外,还阐述了粉煤灰负载壳聚糖和制备沸石分子筛的应用研究,分析总结了粉煤灰吸附剂目前存在的问题,为粉煤灰吸附剂未来的发展方向和资源化利用奠定了理论基础.     

高铁路基中三维排水柔性生态加筋土挡墙施工技术

三维排水柔性生态加筋土挡墙可有效地防护边坡,在表面种植绿色植物又可保护生态环境,发挥挡土墙和植草防护两种边坡防护的优点,其优势是生态环保、施工方便、对不均匀沉降适应性强、稳定性好。介绍某高速铁路站场路基采用的这种边坡防护结构的施工案例。     

Enhancing decision-making flexibility by introducing a new last aggregation evaluating approach based on multi-criteria group decision making and Pythagorean fuzzy sets

Uncertainty is an important factor in any decision-making process. Different tools and approaches have been introduced to handle the uncertain environment of group decision making. One of the latest tools in dealing with uncertainty is Pythagorean fuzzy sets (PFSs). These sets extend the concept of intuitionistic fuzzy sets. To show the advantages of these new sets, this paper offers a novel last aggregation group decision-making process for weighting and evaluating. The methodology employs a new approach in computing the weight of decision makers. Moreover, the concept of entropy is applied to address the fuzziness of weights of evaluation criteria in the process. The method develops a new index in ranking the alternatives. Finally, the proposed method is last aggregation, which means it will be more precise in situations with high variations in decision makers’ judgments. To show the applicability of the method, an example from the literature is adopted and solved for internet companies.     

Robust stabilization of stochastic Markovian jumping systems via proportional-integral control

This paper studied the proportional-integral (PI) control problems of stochastic Markovian jump systems (MJSs) with uncertain parameters. Under complete access to the system states, the PI controller design procedure turns to static output feedback control problem that make the closed-loop dynamics of this class of uncertain MJSs be robustly stochastically stable. A sufficient condition on the existence of PI controller is presented and proved by means of linear matrix inequality techniques. The presented results are extended to the case when the system states are not accessible. In order to make the relative equations approximate with a satisfactory precision, we described the problem as a semidefinite programming one via disciplined convex optimization. Simulation results illustrate the validity of the proposed algorithms.