也谈“八荣八耻”

“八荣八耻”为主要内容的社会主义荣辱观的提出，为当前社会树立了一个新的道德标杆。本文通过对其形式、内容的阐述，强调其通俗易记且寓意深刻，旨在引起人们的重视，并自觉运用“八荣八耻”来规范自己的言行。     

利用参照系简化问题的研究

参照系的选取对描述物体的机械运动形式、运动状态起着重要的作用．     

关于乘幂形式的未定型极限的讨论

本文详细地研讨了几种乘幂形式的未定型极限问题，得到了一些可供直接利用的结果和结论。     

辛差分格式的守恒量及其稳定性

讨论了Ｈａｍｉｌｔｏｎ系统辛差分格式守恒量的存在性问题以及它们与辛差分格式的稳定性间的关系。结果表明，辛差分格式使Ｈａｍｉｌｔｏｎ系统的所有守恒量随时间没有线性变化。一般情况下，差分格式稳定，其守恒量收敛。     

Chevalley基下WZNW场论的Hamilton形式

本文在半单Lie代数的Chevalley正则基下给出了二维WZNW场论的Hamilton形式,并在此基础上计算了守恒流之间的Poisson括号,结果正是经典的Kac-Moody流代数.     

力学量算符的直接函数形式

本文利用一平移算符，给出了离散谱情形下力 学量算符的直接函数形式，它比传统方法简洁．此外， 对于连续谱，情形，也做了简短讨论．     

云计算时代的多样化作业开展策略

以往课外作业以习题训练为主,形式单调,这不利于激发学生的学习兴趣、掌握技能、培养创新能力.云计算的出现为作业形式的多样化产生巨大推力.笔者将基于建构主义、教育心理学的理论,谈谈如何利用云计算实现多样化作业的实现.     

无简并微扰论公式的研究

本文介绍了Ｗｉｇｎｅｒ公式，Ｇｏｌｄｓｔｏｎｅ公式与Ｓｃｈｒｏｄｉｎｇｅｒ公式及其递推形式，比较表明，Ｓｃｈｒｏｄｉｎｇｅｒ公式的递推形式更容易利用计算机程序实现。文中还给出了逐级计算非连通项到任意级的方法。     

浅谈板书优化艺术

板书是教师讲课时在黑板上所写的文字、公式、符号以及所画的图表,它是整个教学思路和内容的浓缩,是课堂教学的重要一环。板书是艺术,对教学效果有直接影响。板书运用得好,可以将课堂活动的重点按一定的形式有系统、有条理地显现在黑板上,帮助学生很好地突破难点、掌握重点,调动学生学习积极性,培养学生的思维能力。     

课堂导入多样性的探讨

课堂导入是一节课的引子和开始的必要环节, 其形式具有多样性. 针对流体压强与流速的关系这节内 容列举5种导入形式, 并分别进行导入技能运用的4个环节示例, 以供参考     

不同应变率下两种岩石的压缩破碎特征试验研究

为了研究不同岩石在不同应变率下压缩时裂纹的产生规律及破坏模式,将石灰岩和红砂岩制成试件,研究其在不同应变率和受力模式下裂纹的形成模式。开展了两种岩石的准静态压缩和动态压缩试验,采用高速摄影机记录了裂纹的产生和破坏模式。对两种岩石试件的裂纹形态进行对比,基于岩石的物理性质、受力状态、能量演化分析,得到了在不同应变率下压缩时产生差异性的原因。结果表明:准静态压缩下岩石试件受压的破坏模式也会因应变率的不同而存在差异,并且破坏模式的差异对岩石试件的抗压强度将产生显著的影响;从能量演化的角度分析,入射能量的大小将会决定岩石试样动态抗压强度曲线是否出现起伏;动态压缩时,裂纹的周向扩展速度与岩石抗压强度呈正相关。     

The Contingency of Laws of Nature in Science and Theology

The belief that laws of nature are contingent played an important role in the emergence of the empirical method of modern physics. During the scientific revolution, this belief was based on the idea of voluntary creation. Taking up Peter Mittelstaedt’s work on laws of nature, this article explores several alternative answers which do not overtly make use of metaphysics: some laws are laws of mathematics; macroscopic laws can emerge from the interplay of numerous subsystems without any specific microscopic nomic structures (John Wheeler’s “law without law”); laws are the preconditions of scientific experience (Kant); laws are theoretical abstractions which only apply in very limited circumstances (Nancy Cartwright). Whereas Cartwright’s approach is in tension with modern scientific methodology, the first three strategies count as illuminating, though partial answers. It is important for the empirical method of modern physics that these three strategies, even when taken together, do not provide a complete explanation of the order of nature. Thus the question of why laws are valid is still relevant. In the concluding section, I argue that the traditional answer, based on voluntary creation, provides the right balance of contingency and coherence which is in harmony with modern scientific method.     

Vectorial approach of determining the wave propagation at metasurfaces

Vector approach often benefits optical engineers and physicists, and a vector formulation of the laws of reflection and refraction has been studied (Tkaczyk, 2012). However, the conventional reflection and refraction laws may be violated in the presence of a metasurface, and reflection and refraction at the metasurface obey generalized laws of reflection and refraction (Yu et al., 2011). In this letter, the vectorial laws of reflection and refraction at the metasurface were derived, and the matrix formulation of these vectorial laws are also obtained. These results enable highly efficient and unambiguous computations in ray-tracing problems that involve a metasurface.     

A general theory of conservation laws,their violation,and spontaneous phenomena

We formulate a general theory of conservation laws and other invariants for a physical system through equivalence relations. The conservation laws are classified according to the type of equivalence relation, with group equivalence, homotopical equivalence, and other types of equivalence relations giving respective kinds of conservation laws. The stability properties in the topological (and differentiable) sense are discussed using continuous deformations with respect to control parameters. The conservation laws due to the Abelian symmetries are shown to be stable through application of well-known theorems.     

渐进多焦点眼用镜片的子午线设计研究

介绍渐进多焦点眼用镜片的构造,论述镜片的设计思想,阐述渐进多焦点眼用镜片子午线设计的基本原理,构建子午线多项式,给出子午线设计需满足的准则.在子午线设计的基础上,设计渐进多焦点眼用镜片等屈光度轮廓线,确定镜片面形,并求出镜片平均球面度与像散.比较3种不同子午线设计的渐进多焦点眼用镜片,并进行实际加工与检测.研究结果表明,子午线设计是渐进多焦点眼用镜片设计的关键之一,不同的子午线屈光度分布,对应的渐进多焦点眼用镜片的球面度、像散以及畸变等差别较大.依据实际设计与检测结果,给出适用于不同个性化需求的渐进多焦点眼用镜片子午线屈光度分布的规律.     

The physicist's role in physical laws

The physicist not only observes phenomena, but he also has an active role in the formulation of some laws. For instance, laws involving irreversibility refer explicitly to what can or cannot be done by physicists. As the abilities of the latter may vary, we obtain sequences of laws, the convergence of which is discussed.     

Generalized Noether identities and application to Yang-Mills field theory

We derive generalized Noether identities for a system with noninvariant action integral under an infinite continuous group and deduce the string conservation laws of the system. We give a preliminary application to field theory and discuss the strong conservation laws for the BRS transformation and the weak conservation laws of Yang-Mills fields. The Dirac constraint of the system is examined.     

Quantum Law of Motion: Analysis and Extension to Higher Dimensions

In this paper, we review the recently formulated quantum laws of motion and provide new observations. We also extend these laws to higher dimensions. By applying in two dimensions the obtained relations to charge submitted to an electric central potential, we decide between these laws. Furthermore, we extend the selected law to the relativistic case in higher dimensions.     

平面火花隙三电极开关研制及性能测试

研制了一种适用于平行板传输连接的平面火花隙三电极开关，开关正负电极为半圆形状，触发电极为细条状。将之替代立体式（半球形电极）火花隙三电极开关并应用于爆炸箔起爆装置中，装置回路参数将得以优化。实验测试了空气间隙为4.12， 3.14和2.2 mm的平面火花隙三电极开关的性能。结果表明，在开关间隙间距一定的情况下，随着电压的升高，开关间隙的放电时延和分散时间呈指数降低，开关电感小于15 nH；对于不同范围内的应用电压，使用不同间隙间距的开关，其分散时间不大于10 ns。该开关应用于较低充电电压（小于10 kV）的脉冲功率装置中，与立体式火花隙三电极开关相比，回路电感降低了约50 nH，放电周期缩短近1/3，峰值电流增加约1/3。     

相对性原理对普遍定律和非普遍定律参考系变换性质的不同要求——关于协变性疑难的进一步讨论

提出普遍定律和非普遍定律以及“协变”与“可导出”的明确定义，证明狭义相对性原理（及其伽利略近似）要求在惯性系变换下，自然界普遍定律是协变的，非普遍定律不协变但是“可导出”的，一切定律都服从相对性原理，从而进一步解答了由爱因斯坦，朗道关于狭义相对性原理的一种错误表述所引起的“协变性疑难”，还将有关结论推广到广义相对性原理情况。