基于ATMega16L的矿用锚杆静态电阻应变仪设计

为了检测煤矿巷道支护体受力状况,介绍了一种矿用锚杆静态电阻应变仪。该应变仪采用ATMega16L作为主控芯片,包括硬件电路及软件部分的设计,硬件上采用电子程控开关切换、精密仪表放大器和先进低频滤波等对信号采集调理,并采用LCD汉字显示检测结果;软件上下位机利用AVR单片机的输入捕捉、CTC模式、I2C等功能。实验结果表明:矿用锚杆静态电阻应变仪精度高、电路简单、汉字显示,具有较高的抗干扰能力;在测量煤矿巷道支护构件(锚杆、锚索)所受应力大小的工作中,给井巷锚固工作带来了更便携的测试手段。     

de Sitter空间中具有平行单位平均曲率向量的完备类空子流形

利用Yau的广义极大值原理,给出了de Sitter空间中具有平行单位平均曲率向量的完备类空子流形Mn是全脐子流形的充分条件。     

Effect of Testing Conditions on Fibre-Bundle Tensile Properties-Part Ⅱ: the Gauge Length and Elongation Speed in Wool Fibre Bundle Measurement

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千分表的检定及修理

分析了千分表的结构及其工作原理，并简单介绍了千分表示值误差的检定方法及常见故障的维修措施。     

球对称度规场中的质量亏损效应

得到了一类带荷天体在含宇宙常数的重力场，即Reissner-Nordstrom-de Sitter场中的质量亏损效应的几个表达式，通过讨论这些表达式中的参数，得到了在其他几种场中和不同条件下的质量亏损．这些是天文学中关于天体形成过程辐射出去能量的有意义的求解方法．     

From proportion to balance: the background to symmetry in science

We call attention to the historical fact that the meaning of symmetry in antiquity—as it appears in Vitruvius’s De architectura—is entirely different from the modern concept. This leads us to the question, what is the evidence for the changes in the meaning of the term symmetry, and what were the different meanings attached to it? We show that the meaning of the term in an aesthetic sense gradually shifted in the context of architecture before the image of the balance was attached to the term in the middle of the 18th century and well before the first modern scientific usage by Legendre in 1794.     

de Sitter空间中的紧致2-调和类时子流形

利用活动标架法,得到了de Sitter空间中的紧致2-调和类时子流形的一个积分不等式以及该子流形成为极大类时子流形的关于其第二基本形式模长平方一个拼挤定理.     

物理世界相互作用定律的内在不变性——从系统科学哲学视角看规范场论

根据规范场论,自然界各种不同的基本相互作用在实质上都归结为规范场,而“规范对称性”的本质在于“物理定律在变换中保持内在不变性”。按照一般系统论的“不同科学中的同构性”的思想,这种“变换中的不变性”可以推广到包括经济系统和生命系统在内的最一般的系统中去。     

《直说通略》中的助词“得”

就《直说通略》中助词“得”的使用格式、语法功能等几个方面对其进行横向描写和纵向对比,以理清《直说通略》所处时代助词“得”的发展面貌和助词“得”的历史发展脉络,明了蒙古语对汉语助词“得”的发展所产生的影响。     

Octopus mimicking its follower reef fish

We describe a possible example of social mimicry between Octopus insularis and the small grouper Cephalopholis fulva, which frequently associate during foraging at Fernando de Noronha Archipelago, Brazil. The octopus, when swimming backwards, jet‐propelled, becomes similar in colour and shape to accompanying C. fulva individuals and is therefore less conspicuous within the fish group. We regard this as an instance of social mimicry, a form of protection against visually‐oriented predators in which different species similar in shape and colour mingle for the advantage of grouping. Even when swimming backwards alone, O. insularis may become similar to foraging C. fulva individuals, another putatively protective behaviour. We suggest that the feeding association commonly found between O. insularis and C. fulva minimized the evolutionary costs for the origin of mimicking by the octopus.