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1.
在阐明《共产党宣言》中对社会主义和共产主义文献的分析的基础上,着重论述了这种分析的当代意义,使我们再次品味《共产党宣言》的永不磨灭的价值。  相似文献   

2.
本文从数学实验的角度着手,以傅立叶级数和曲线族的包络实验为例,从一个侧面探讨数学教学与物理教学之间的关系。为高校的教学改革提供了新的视角。  相似文献   

3.
师生关系与学校教育教学工作息息相关。了解高等院校师生关系现状、成困 ,研究改进对策 ,对于做好教书育人工作 ,培养合格专门技术人才具有重要的现实意义。  一、高等院校师生关系的现实意义现在许多高等院校的老师都觉得师生关系冷淡 ,有时师生见面互不搭理 ,形如路人一般。那学生的感受又是怎样的呢 ?笔者调查了一千多大学生 ,结果表明 :认为师生关系“很密切”的学生只占 0 .7% ,认为“较密切”的学生占有 14 .2 % ,认为“较冷淡”的学生却占到了 74 .1% ,认为“很冷淡”的学生也占到了 11%。可见 ,和教师的感受一样 ,较大多数的学生…  相似文献   

4.
The recent development of several new observational techniques as well as of advanced computer simulation codes has contributed significantly to our understanding of dynamics of the three-dimensional current system during magnetospheric substorms. This paper attempts to review the main results of the last decade of research in such diverse fields as electric fields and currents in the high-latitude ionosphere and field-aligned currents and their relationship to the large-scale distribution of auroras and auroral precipitation. It also contains discussions on some efforts in synthesizing the vast amount of the observations to construct an empirical model which connects the ionospheric currents with field-aligned currents. While our understanding has been greatly improved during the last decade, there is much that is as yet unsettled. For example, we have reached only a first approximation model of the three-dimensional current system which is not inconsistent with integrated, ground-based and space observations of electric and magnetic fields. We have just begun to unfold the cause of the field-aligned currents both in the magnetosphere and ionosphere. Dynamical behaviour of the magnetosphere-ionosphere coupling relating to substorm variability can be an important topic during the coming years.On leave of absence from Kyoto Sangyo University, Kyoto 603, Japan.  相似文献   

5.
轴承预紧力与系统固有频率关系的试验   总被引:1,自引:0,他引:1  
研制了轴承预紧力测试装置,通过该试验装置对预紧力和系统固有频率的关系进行了研究.对轴承预紧力随系统固有频率变化的试验数据进行了拟合.结果表明:该试验装置从一定程度上反映了轴承的预紧特性.固有频率随轴承预紧力的增大而增大,相同的预紧力下,系统固有频率随轴承支承跨距的增大而增大.拟合得到的预紧力-固有频率-支承跨距关系式精度较高.   相似文献   

6.
本通过对萨丕尔--沃尔夫假设的陈述,旨在分析语言与社会化的关系,从而指出正确处理这两的关系可以帮助我们准确地进行社会交往。  相似文献   

7.
Target motion modes have a close relationship with the relative orientation of missile-totarget in three-dimensional highly maneuvering target interception. From the perspective of relationship between the sensor coordinate system and the target body coordinate system, a basic model of sensor is stated and the definition of relative angular velocity between the two coordinate systems is introduced firstly. Then, the three-dimensional analytic expressions of relative angular velocity for different motion modes are derived and simplified by analyzing the influences of target centroid motion, rotation around centroid and relative motion. Finally, the relationships of the relative angular velocity directions and values with motion modes are discussed. Simulation results validate the rationality of the theoretical analysis. It is demonstrated that there are significant differences of the relative orientation in different motion modes which include luxuriant information about motion modes. The conclusions are significant for the research of motion mode identification,maneuver detection, maneuvering target tracking and interception using target signatures.  相似文献   

8.
以GH4169合金大规格棒材为研究对象,结合棒材的加工过程,利用OM、FE-SEM、EBSD和TEM等手段分析了该合金不同晶粒尺寸试样的持久性能。结果表明:在长时高温应力作用下,不同晶粒尺寸试样呈现不同的持久性能和不同的晶粒取向演变规律。发生变形至断裂的位置,晶粒尺寸较小时,部分〈101〉取向明显转向〈001〉或〈111〉取向,加上宏观变形协调性较好,促使应力集中得到有效释放,表现出较好的塑性;但细晶试样中更多晶界带来的扩散蠕变对高温强度不利,裂纹也容易在与〈111〉硬取向晶粒接邻的晶界处形核并扩展,降低持久寿命;此外,细晶试样的变形程度较大,应变主要集中于晶界处,且大角度取向差的含量较多,这些位置容易萌生裂纹而使寿命降低。  相似文献   

9.
民航安全管理与风险管理的关系   总被引:1,自引:0,他引:1  
根据国际民航公约附件1、6、8、11、13、14条,以及国际民航组织有关文件要求,安全管理体系作为国家安全纲要(SSP)的组成部分,各缔约国应强制要求已获批准的且在提供服务时面临安全风险的培训组织、航  相似文献   

10.
金融危机全球拯救行动全面展开,"救市"的方法却惊人的相似.由于"救市"之急迫在眉睫,西方各国不得不暂时淡化以往的意识形态之争,把马克思主义公有制的核心理论之一"国有化"付诸于实践,以解救市之急.金融海啸过后,意识形态之争必将在新的层面拉开,在昔日被视为"毒蛇猛兽"的共产主义的"幽灵"变成了普世的"菩萨"之后,主义之争会更加残酷,共产主义的历程依旧遥远,我们对共产主义的景仰和追求也会因这场经济的血与火的洗礼而升华到一种更高的境界.  相似文献   

11.
对航空发动机技术水平提高速度与投资强度这两个概念做了界定.利用有关数据,针对航空涡轮发动机的技术水平提高速度、最大推力、类型(涡喷或涡扇)与投资强度的定量关系建立了的一个数学模型,并对模型的应用进行了探讨.  相似文献   

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