一维铁磁链中的磁隙孤子激发

采用Holstein-Primakoff变换、相干态表示；含时微扰原理和多重标度方法，研究了Aharonov-Bohm(A-B)磁通对一维铁磁链中的磁隙孤子产生的影响，得到了在A－B磁通影响下的磁隙孤子的峰值、宽度、能量和自旋空间排列。     

电磁感应定律两种表述的讨论

电磁感应定律的两种表述,形式简单,意义明确,并且可以互导。但由于它们的推导是有条件、有侧重的,所以把握这些条件与特征,对于清晰理解它们各自的适用范围帮助很大。     

带电粒子在磁场中的运动和能量

研究了带电粒子分别在均匀磁场、均匀变化磁场中的运动和能量。     

用移动磁场分析电度表的工作原理

从移动磁场的产生入手,分析了电度表的工作原理。     

单相小功率工频稀土永磁发电机组的设计与性能分析

工频稀土永磁发电机的气隙磁场是由稀土永磁体提供,具有功率密度大、体积小、结构简单等特点.介绍了单相小功率（4kVA）工频稀土永磁发电机组的设计,通过采样REPMG端电压信号反馈自动调节油机转速,以及采用非均匀气隙长度分布设计永磁发电机的极靴形状,实测样机的性能表明其具有电压波形畸变率和电压变化率小的特点.     

磁感应强度的新定义及磁学定律的理论推导

电荷的运动产生磁场,磁力是运动电荷在磁场中所受到的作用力,在经典电磁学理论中,磁感应强度的定义不能全面反映上述磁性起源的微观本质。我们试图寻求一种新的定义形式,既说明磁场由电荷运动产生,又说明磁力是运动电荷所受到的作用力,并由此出发,在理论上推导出磁场的全部实验定律和静电学的库仑定律。     

宁夏师范学院学生体育消费现状调查研究及分析

运用问卷调查法、数理统计法、文献资料法、访谈法等方法对宁夏师范学院学生体育消费进行了调查研究,了解宁夏师范学院学生体育消费的现状,其目的在于有针对性地分析影响我校大学生体育消费行为的主要因素,为推动体育产业的开发及我校体育事业的发展提供理论依据.结果表明,影响我校学生体育消费行为的主要因素有：经济能力有限、缺乏体育场馆设施、消费价格高及对体育的爱好程度.     

抗磁效应测试方法研究

探讨了抗磁效应在经典物理范畴中的成因,并导出了其测量原理,依据该原理设计了一个简单易行的测试仪器,能对很难观察到的抗磁效应作定量测试,并说明了有关的注意事项．     

Review: Research progress on Fabry-Perot resonator antenna

The Fabry-Perot resonator (FPR) antenna has found wide applications in microwave and millimeter waves and recently attracted considerable interest, in this paper, a summary of planar and cylindrical structures, analytic models and research development is presented, and a comparison between these structures and analytic models is made, showing that such analytic models as the FP cavity mode, electromagnetic band gap (EBG) defect mode, transmission line mode, and leaky-wave mode are consistent when applied to analyze this type of resonator antenna. Some interesting topics under recent research, including dual or multi-band, improvement of gain bandwidth, low profile and beam control, are surveyed.     

The relationship between muscle cross-sectional area and strength in various isokinetic movements among soccer players

Abstract

The aim of the present study was to examine the relationships between muscle cross-sectional area (CSA) and muscular strength in terms of knee extension and flexion, hip extension and flexion, and hip abduction and adduction among well-trained soccer players. Fourteen university soccer players participated in the study, who had previously been divided into two groups based on ability (Group A: above-average ability; Group B: average ability). Maximal isokinetic and concentric muscular strength was measured in knee extension/flexion, hip extension/flexion and hip abduction/adduction using an isokinetic dynamometer at 1.57 and 4.19 rad·s^?1 (3.14 rad·s^?1) in both the dominant and non-dominant leg. The CSAs of the thigh, gluteus muscles and iliopsoas muscles were calculated based on magnetic resonance imaging. There was no significant difference between the two groups in muscle CSA and isokinetic strength. Although there were some statistically significant differences between the dominant and non-dominant leg in terms of CSA and strength (P<0.05–0.01), these were small and negligible. Apart from a non-significant relationship between the CSAs of the adductor muscles and hip adductor strength (r<0.26, n.s.), the CSA of the other muscle groups correlated with maximal isokinetic strength (r=0.38–0.64, P<0.05). These results suggest that no difference in muscle characteristics (in terms of muscle CSA and strength) was apparent among well-trained soccer players, even between the dominant and non-dominant leg. There is also a case that the anatomical function of a single (or group of) muscle(s) may not be reflected by the strength—CSA relationship depending on the movements (such as hip adduction-adductor muscle CSA). Thus, further studies are required to develop methods to assess neuromuscular function in relation to muscle morphology among soccer players.