PSA/BAS水刺滤料过滤性能研究

以玄武岩纤维(BAS)机织布为底层,芳砜纶(PSA)为面层,采用水刺工艺使二者结合制得PSA/BAS水刺滤料.测试了PSA/BAS滤料的过滤性能,并与100％ PSA针刺滤料和BAS机织布进行对比,分析了PSA/BAS水刺滤料用于袋式除尘的技术特点.结果表明:在不同过滤速度下,清洁PSA/BAS水刺滤料对粒径≥6μm颗...     

腰部外骨骼机器人线性自抗扰控制器参数优化

针对腰部外骨骼机器人线性自抗扰控制器参数难以调整的问题,本文提出一种基于天牛须搜索的改进粒子群算法(PSO)。建立腰部外骨骼机器人模型,采用线性自抗扰控制器,进一步引入改进的PSO对其进行参数优化。该算法通过混沌初始化种群,提高粒子执行效率;采用非线性策略调整惯性因子和学习因子,加强粒子的搜索能力;引入天牛须搜索算法与PSO结合,并采用自适应权重,使得粒子可对周边环境进行较好地判断,避免粒子陷入局部最优。分别通过6个测试函数和建立系统评价指标进行仿真实验,结果表明所提出的算法有更好的收敛精度,优化后的控制器具有更好的控制性能。     

自适应BAS优化RBF神经网络的短时交通流预测

为提高短时交通流预测精度,针对传统径向基函数(radial basis function, RBF)神经网络短时交通流预测模型中心值固定、易受漂移数据干扰问题,提出自适应天牛须搜索算法(beetle antennae search algorithm, BAS)优化RBF神经网络的短时交通流预测模型。模型采用自适应步长提高BAS算法迭代速度和寻优能力,结合DBSCAN聚类确定RBF神经网络隐含层径向基函数网络中心,进而优化神经网络结构。通过路网真实交通流数据进行训练,选择常用于短时交通流预测的BP神经网络,RBF神经网络,广义RBF神经网络进行对比。结果表明：优化后的模型预测结果相较BP神经网络平均绝对误差降低了1.87%、平均绝对百分比误差降低了15.96%、均方根误差降低了3.24%,拟合度提高了3.96%;相较广义RBF神经网络平均绝对误差降低1.36%、平均绝对百分比误差降低了5.01%、均方根误差降低了2.19%,拟合度提高了2.5%。改进后的短时交通流预测模型能够为智能交通诱导提供可靠的预测值。     

Densification and phase transformation of Si3N4 in the presence of mechanically activated BaCO3–Al2O3–SiO2 mixture

Densification as well as the →β phase transformation of Si₃N₄ were monitored as a function of activation time of the BaCO₃–Al₂O₃–SiO₂ additive mixture. The composition of the ternary mixture corresponded to celsian (BaAl₂Si₂O₈—BAS). Previously, mechanically activated powder mixtures for various lengths of time were added to Si₃N₄ in the amount of 10–30%. Sintering was performed at 1650–1700°C in nitrogen atmosphere up to 8 h. The changes in densification degree, as well as phase composition, were followed as a function of heating time and the time of mechanical activation of the additive mixture. The results obtained showed that mechanical activation retarded densification in samples heated up to 1700°C. On the other hand, for the constant sintering time, →β transformation of Si₃N₄ was enhanced with increasing activation time, and the amount of additives.     

Microstructure and mechanical properties of SiC platelet reinforced BaOAl2O32SiO2 (BAS) composites

BaOAl₂O₃2SiO₂ (BAS) glass–ceramic powders were prepared by sol–gel technique. SiC platelet reinforced BAS glass–ceramic matrix composites with high density and uniform microstructure were fabricated by hot-pressing. The effect of additional crystalline seeds on hexagonal to monoclinic phase transformation of Barium aluminosilicate was studied. The effects of SiC platelet content on the microstructure and mechanical properties of the composites were also investigated. The results showed that the flexural strength and fracture toughness of the BAS glass–ceramic matrix composites can be effectively improved by the addition of silicon carbide platelets. The main toughening mechanism was crack deflection, platelets' pull-out and bridging. The increased value of flexural strength is contributed to the load transition from the matrix to SiC platelets.     

西安某大厦空调自控系统设计

介绍了Seimens System 600 Spogee 顶峰系统在某大厦空调自控系统中的应用,同时介绍了各控制系统的组成,最后叙述了在系统安装及调试过程中的体会.     

楼宇自控系统的专业化与系统集成

根据智能建筑楼宇自控系统的内容,结合某一具体工程实例,对其专业化的体现进行了详细的分析.论述了楼宇自控系统设计的指导原则,阐述了楼宇自控系统的集成方式.提出智能建筑的楼宇自控系统应与办公自动化系统、通信自动化系统一体化实现.     

医院建筑设备自动监控系统设计

根据现代化医院的特点,以某医院的工程项目为例,介绍了医院建筑设备自动监控系统的设计。通过对该系统经济效益的分析,说明了建筑设备自动监控系统在医院建筑节能中的重要作用。     

SynchroIBMS在智能建筑物联网应用平台中的作用

介绍了协同智能建筑集成管理平台（SynchroIBMS）和智能建筑物联网应用平台的原理、组成、功能及关键要素;同时对SynchroIBMS在智能建筑物联网应用平台中的作用作了简要的阐述,最后对SynchroIBMS在行业中的应用提出了展望。     

宽带接入服务器备份和负载分担网络方案的研究

由于弹性分组环具有快速自愈、业务分级等特性,论文以此为基础提出了实现宽带接入服务器备份和负载分担的城域网解决方案,并通过实验数据验证了这一解决方案的有效性。