摘要：文中研究基于多正弦扰动信号注入的大功率并网逆变器电网阻抗测量技术。选取多正弦信号作为电压扰动,参考空间光场理论中的Gerchberg-Saxton相位恢复算法对扰动信号进行优化设计;剪辑函数作为其中的关键要素,能够决定扰动信号时域波峰的剪辑速度和剪辑能力;为提升上述性能,提出采用反正切函数代替传统算法中的对数剪辑函数,仿真结果表明,相位恢复算法的剪辑性能得到大幅提升;随后,通过逆变器将扰动信号注入电网,采用Gauss-Newton非线性最小二乘法对采集到的扰动信号特征谐波频率点的信息进行曲线拟合,获取当前电网阻抗信息;最后,于搭建的1.5 MW并网逆变器RT-Lab平台进行多弱电网场景下的阻抗测量实验,实验结果验证了此方案的有效性和准确性。

摘要：目的:探究额顶叶θ-经颅交流电刺激(theta-transcranial alternating current stimulation,θ-tACS)对健康成年人不同姿势条件下(坐位和站立位)工作记忆表现的影响。方法:本研究为随机、交叉、双盲设计。选取16名健康成年人,以随机顺序进行tACS真刺激和假刺激,两次刺激之间至少间隔72h。tACS方案使用7个电极放置于左侧额顶叶振荡关键脑区,频率选择为6Hz,持续21min。假刺激方案使用与tACS真刺激方案相同的刺激靶区、频率,但只进行1min的刺激(刺激开始和结束各30s)。在刺激前和刺激后即刻评估坐位及站立位n-back工作记忆表现,包括正确率、反应时和逆效率得分。采用Wilcoxon秩和检验观察刺激方式对工作记忆影响的组间及组内差异。结果:15名受试者完成试验,两种刺激条件均未出现明显副作用和不良反应。额顶叶θ-tACS后,坐位工作记忆的反应时、逆效率得分与站立位的反应时改善显著(P0.05)。结论:额顶叶θ-tACS可以改善坐位和站立位不同姿势下的工作记忆表现,有助于健康成年人应对现实生活中的多任务认知活动,具有重要的实践应用价值。

摘要：针对自动调节泡沫混合装置操作复杂,控制效果和控制精度差等缺点,提出了一种基于神经网络PID算法的负压环泵式泡沫混合装置控制方法,并以此为基础设计了一套消防车用泡沫比例控制系统。分析并设计了合理的泡沫混合系统;设计了人性化的人机交互界面;PLC控制器可根据操作指令和车辆状态自动实现泡沫混合液的喷射;采用神经网络PID算法控制吸泡沫比例阀的开度,实现对泡沫混合液的泡沫比例的精准控制。实验证明:该系统能够实现一键操作和自动控制,可稳定的输出混合比例为3%~6%的泡沫混合液,控制精度超过国家标准规定。

摘要：考虑了学习效应对流水车间调度问题的影响,以最大完工时间和总加权滞后时间为优化目标,建立了与加工顺序相关的对数线性调度模型,设计了LNEH(NEH heuristic with Learning effect)启发式算法和MCF(Membrane Computing for multi-objective Flow-shop scheduling)算法进行求解。LNEH算法根据对学习效应下问题性质的分析,在初始序列和工件插入两个环节进而达到对原有NEH算法的改进,同时采用随机策略以获得多个解。MCF算法是采用膜计算理论设计的一种近似调度优化算法,针对调度问题设计了字符对象的编码方式,根据前端等级大小将字符对象往复地分配为均匀的对象集,借鉴PSO算法制订膜内规则:从外部档案和所在的基本膜内中分别选择作为参考的选择规则和类似于PSO算法的移动规则。数值仿真显示,不同学习系数对调度结果具有较大影响,并对比证明了所提两种算法的有效性。

摘要：左金丸为中医治疗肝火犯胃证的经典方剂,具有降血压、抗抑郁、抗溃疡、抗肿瘤、抗炎抑菌镇痛、抗幽门螺杆菌、调节胃肠运动以及中枢系统等多种药理作用,临床多通过原方加减或联合西药用于慢性胃药、消化性溃疡、胃食管反流病、溃疡性结肠炎、幽门螺杆菌感染等疾病的治疗。目前,对左金丸的活性成分研究以单味药物报道为主,缺乏对其复方有效化学成分的研究,且左金丸制作工艺与质量控制缺少统一标准,今后亟须进行更为严谨的实验设计,加强大样本的随机对照试验研究,必要时联合多学科开展实验,以全面揭示左金丸的临床效用机理,为扩大左金丸的临床应用提供强有力的证据。

摘要：基于远程智能气象站的技术手段,可以提升配网线路杆塔带电作业的效率。分析配网线路带电作业所面临的问题和挑战,重点关注作业点勘查和气象条件确认的流程。介绍设计与功能方面的远程智能气象站,包括设计要求、技术参数以及各监测及测量模块的功能介绍。针对提升效率的策略,提出了可视远程智能气象站、远程实时监测作业点气象环境、优化人员车辆分配、减少无效计划分配以及提高作业前期勘查效率等措施,并就远程智能气象站在实际带电作业中的应用前景展开讨论。

摘要：Multi-pylon multi-span suspension bridge is a new type super flexible structure system, and the rigidity design of middle pylon is one of the main difficult technical issues. Due to the requirements of longitudinal rigidity, the structural form and the corresponding foundation type of middle pylon are different from those of the ordinary steel pylon, and the complicated dynamic characteristics make the calculation quite difficult. In this article, exploration has been made in selection of similarity ratio and model materials, section simulation, restriction conditions simulation, fixing of mass blocks, fabrication scheme and testing method by taking into account different construction and working conditions such as restriction conditions and working environment of a three-pylon suspension bridge, to conduct the test experimental design of the dynamic behavior of the middle pylon, with the purpose to reveal its dynamic characteristics and make comparison and analysis with theoretical assumptions, to provide basis for anti-wind and anti-seismic design and reference for the design and research of three-pylon two-span suspension bridges in the future.

摘要：由于智能电网负荷频率和负荷电压调节向量不确定,难以实现智能电网负荷协同调度,因此,提出基于混合粒子群优化的智能电网负荷协同调度方法。根据混合粒子群优化条件,求解电网负荷协同调度中的优化参数,定义目标负荷函数。分别计算智能电网负荷频率与负荷电压调节向量,结合电量信号确定协同调度决策指标的取值范围,实现智能电网负荷协同调度。实验结果表明,所提方法应用下,电量信号传输功率极值之差不超过100 dBm,满足智能电网负荷协同调度的实际应用需求。

摘要：The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking *** this study,the interaction between calcium carbonate and iron ore powder and the mineralization mechanism of fluxed iron ore pellet in the roasting process were investigated through diffusion couple *** electron microscopy with energy dispersive spectroscopy was used to study the elements’diffusion and phase transformation during the roasting *** results indicated that limestone decomposed into calcium oxide,and magnetite was oxidized to hematite at the early stage of *** the increase in roasting temperature,the diffusion rate of Fe and Ca was obviously accelerated,while the diffusion rate of Si was relatively *** order of magnitude of interdiffusion coefficient of Fe_(2)O_(3)-CaO diffusion couple was 10^(−10) m^(2)·s^(−1) at a roasting temperature of 1200℃for 9 ***_(2)Fe_(2)O_(5) was the initial product in the Fe_(2)O_(3)-CaO-SiO_(2) diffusion interface,and then Ca_(2)Fe_(2)O_(5) continued to react with Fe_(2)O_(3) to form CaFe_(2)O_(4).With the expansion of the diffusion region,the sillico-ferrite of calcium liquid phase was produced due to the melting of SiO_(2) into CaFe_(2)O_(4),which can strengthen the consolidation of fluxed ***,andradite would be formed around a small part of quartz particles,which is also conducive to the consolidation of fluxed *** addition,the principle diagram of limestone and quartz diffusion reaction in the process of fluxed pellet roasting was discussed.

摘要：作业是课程和教学的重要组成部分。从单元教学全过程视角对作业进行系统化设计,有助于发挥作业特有的育人功能。嵌入式系统化作业是指嵌入教学全过程、融通课堂内外、形成协同育人合力的一系列作业,包括单元作业和课时作业。其中的课时作业又由若干功能各异的诊断反馈作业、定向矫正作业和巩固拓展作业构成。中学物理学科嵌入式系统化作业的设计应关注目标拟定、情境创设、素材挖掘、任务提炼等方面。