"电磁场与电磁波"课程的教学研究

电磁场与电磁波是电气、电子信息、通信等各类本科专业学生必修的一门主干课程,基于该课程的特点,结合自身对本门课的教学研究,从教学大纲的制定、理论教学手段的改进、实践教学的开展等方面进行了系统的讨论,实践证明这些方法有益教学质量的提高。     

体目标射频回波信号实时仿真方法研究

讨论了四种射频回波信号实时仿真方法,即：使用专用硬件加速卡的射频回波信号实时仿真;使用多机系统的射频回波信号实时仿真;基于部分射频回波数据的实时内插或外推;利用ISAR像提取目标的主散射中心进行目标射频回波信号的实时计算。比较了四种实时仿真方法的异同。     

民俗类文本的语言特色及其译介分析

基于能量守恒及传热学的基本理论，建立了电加热地板辐射采暖启动过程的数学模型，开发了用于预测各特征点温度随启动时间变化的计算软件。特征点分别为室内空气温度、地板上、下表面温度，屋顶的内、外表面温度，以及围护结构内、外表面的温度。为了验证程序的合理性，针对同一供暖房间，利用所开发的软件进行了计算并进行了实际测量。结果表明：软件计算值与实测值在合理的误差范围内。利用该软件，综合分析了加热功率、发热电缆覆盖层厚度、围护结构特性以及室外温度等因素对供暖房间升温速率的影响。     

A Potts‐mixture spatiotemporal joint model for combined magnetoencephalography and electroencephalography data

We develop a new methodology for determining the location and dynamics of brain activity from combined magnetoencephalography (MEG) and electroencephalography (EEG) data. The resulting inverse problem is ill‐posed and is one of the most difficult problems in neuroimaging data analysis. In our development we propose a solution that combines the data from three different modalities, magnetic resonance imaging (MRI), MEG and EEG, together. We propose a new Bayesian spatial finite mixture model that builds on the mesostate‐space model developed by Daunizeau & Friston [Daunizeau and Friston, NeuroImage 2007; 38, 67–81]. Our new model incorporates two major extensions: (i) We combine EEG and MEG data together and formulate a joint model for dealing with the two modalities simultaneously; (ii) we incorporate the Potts model to represent the spatial dependence in an allocation process that partitions the cortical surface into a small number of latent states termed mesostates. The cortical surface is obtained from MRI. We formulate the new spatiotemporal model and derive an efficient procedure for simultaneous point estimation and model selection based on the iterated conditional modes algorithm combined with local polynomial smoothing. The proposed method results in a novel estimator for the number of mixture components and is able to select active brain regions, which correspond to active variables in a high‐dimensional dynamic linear model. The methodology is investigated using synthetic data and simulation studies and then demonstrated on an application examining the neural response to the perception of scrambled faces. R software implementing the methodology along with several sample datasets are available at the following GitHub repository https://github.com/v2south/PottsMix . The Canadian Journal of Statistics 47: 688–711; 2019 © 2019 Statistical Society of Canada     

一种新型结构磁流变阻尼器

提出了一种新型结构的磁流变阻尼器，该阻尼器主要包括内层缸筒、外层缸筒和线圈组件，其中线圈组件固定于外层缸筒的外侧，电磁线圈不与磁流变液接触，具有装拆方便、容易维护、散热良好、能够提高磁流变阻尼器活塞的有效行程等优点。采用ANSYS软件建立新型结构磁流变阻尼器的电磁场有限元模型，将电磁场理论分析值和有限元分析值进行比较，分析结果表明，外层缸筒和线圈组件的特殊结构，能够保证磁流变液流动通道内产生有效磁场。     

Implicit Attitudes Toward Nuclear Power and Mobile Phone Base Stations: Support for the Affect Heuristic

The implicit association test (IAT) measures automatic associations. In the present research, the IAT was adapted to measure implicit attitudes toward technological hazards. In Study 1, implicit and explicit attitudes toward nuclear power were examined. Implicit measures (i.e., the IAT) revealed negative attitudes toward nuclear power that were not detected by explicit measures (i.e., a questionnaire). In Study 2, implicit attitudes toward EMF (electro-magnetic field) hazards were examined. Results showed that cell phone base stations and power lines are judged to be similarly risky and, further, that base stations are more closely related to risk concepts than home appliances are. No differences between experts and lay people were observed. Results of the present studies are in line with the affect heuristic proposed by Slovic and colleagues. Affect seems to be an important factor in risk perception.     

麦克斯韦与物理学的发展

本文主要从电磁场理论和气动理论两个方面阐述了麦克斯韦对物理学发展所做出的巨大贡献。     

基于模型的JN60型焦炉加热控制

介绍了JN60型焦炉的加热控制研究与应用,并采用了火道温度串级控制和烟道吸力的前馈控制的系统控制方案与模糊控制策略,建立了相关的控制数学模型和工艺模型,利用计算所得的炼焦指数为在线参数对焦炭质量指标进行控制。系统运行结果表明节能约3.5%左右,炉温平均波动小于3℃,安定系数均在0.95以上。     

利用混沌提高dc/dc变换器的EMC性能

为了提高dc/dc变换电源的电磁兼容性,基于混沌现象的宽频谱特性提出了一种新的dc/dc变换器控制策略。首先推导了能够产生可控幅度混沌序列的Logistic映射形式,然后利用混沌序列对电流滞环控制策略的电流参考值进行扰动。从而扩展了电感电流的功率谱,降低了在开关频率及其谐波频率上发射的电磁干扰。仿真研究证明,该控制策略可以改善dc/dc变换器的电磁兼容性能。     

长辐旋轮线是带电粒子在磁场运动的又一轨迹

定量分析文献 [2 ]所给带电粒子在电磁场中运动的一个实例 ,得出其正确运动轨迹。