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1.
姜玉亭 《科技信息》2010,(23):34-34,91
从培养学生的自主学习能力出发,对一阶RC电路阶跃响应实验进行改革,引导学生逐步理解并掌握RC电路的阶跃响应过程,并能够在给定条件下,自己设计RC积分和微分电路。  相似文献   

2.
基于抗剪机构和破坏模式的RC剪力墙极限承载力分析   总被引:1,自引:0,他引:1  
以建立基于抗剪机构和破坏模式的钢筋混凝土(RC)剪力墙极限承载力的分析模型为目的,根据RC剪力墙破坏模式,剪力墙的抗剪机构可简化成倾角为θ的混凝土压杆、纵向及横向分布钢筋3部分。基于该抗剪机构,推导了RC剪力墙的极限承载力的计算公式,并编制了计算程序,对15片不同配筋、不同几何尺寸和受力状态的RC剪力墙进行了承栽力分析,理论计算结果和试验结果吻合较好,该分析模型能够较好地反映RC剪力墙的极限承载力特性,可供RC剪力墙抗剪强度验算参考。  相似文献   

3.
用数学的方法,结合拉普拉斯变换解出了RC串联电路的特征值,无论是在直流状态下,还是在交流状态下,均可得到和经典结论一致的满意结果,这一计算方法,弥补了电工书籍中对RC串联电路理论推导内容的不足.  相似文献   

4.
基于RC6的改进加密算法   总被引:1,自引:1,他引:0  
对适合在IC卡上实现的加密算法RC6进行了详细的分析,并在此基础上对RC6算法本身存在的缺陷进行了改进,所得结果,解决了IC卡管理系统中的核心安全问题,即对IC卡中效据的加密问题具有一定的意义。  相似文献   

5.
近年来采用电阻——电容装置(简称RC装置)限制真空开关操作过电压方法得到了重视。用RC装置可以把过电压降到电机2.6倍相电压以下,还可以有效地保护匝间绝缘。  相似文献   

6.
钢筋混凝土(Reinforced Concrete, RC)结构在遭受火灾高温后力学性能发生损伤退化.为了探究碳纤维增强复合材料(Carbon Fiber Reinforced Polymer, CFRP)加固高温损伤RC板的力学性能,基于“热学-力学”顺序单向耦合框架,开展了三维数值模拟.在模拟中,首先进行高温条件下RC板传热分析,获得其温度场变化;进而考虑钢筋和混凝土材料力学性能以及二者之间非线性粘结-滑移行为随温度的退化规律,假定外贴CRFP片材与混凝土之间的相互作用为完好粘结,建立CFRP加固高温损伤RC板三维有限元分析模型.在验证了三维数值模型合理性的基础上,分析了不同高温时间损伤RC板外贴CFRP加固后的破坏形态、承载力、挠度、刚度和内部应变等,评估了加固效果,进一步讨论了CFRP条带粘贴数量对加固效果的影响.结果表明:RC板受火后在四点加载下的破坏模式为典型弯曲破坏.随着受火时间增加,损伤更加严重,承载力和刚度等逐渐降低,钢筋和CFRP的应变增大.随着RC板高温损伤后粘贴CFRP层数增加,承载力和刚度增大,钢筋和CFRP的应变降低.此外,当板受火时间达到耐火极限90min...  相似文献   

7.
RC和RL电路在充、放电过程中,消耗在电阻R上的能量与R的大小无关,而充、放电的快慢则与R有关,体现在电容性时间常数r=RC和电感性时间常数r=L/R中。  相似文献   

8.
橡胶混凝土(concrete with rubber aggregate,RC)具有较高的抗冻融性,但其在各种冻融条件下的长期蠕变行为尚不清楚,势必会影响橡胶混凝土在严寒地区的应用.以RC在冻融循环条件下的蠕变特性为对象,选取C40普通混凝土配比为试验基准,将等体积、粒径为3~6 mm橡胶颗粒代替中砂质量的10%配制了...  相似文献   

9.
本文利用拉氏变换法求解了两个RC二阶电路的阶跃响应.从对响应的分析中得出了电容量在线测量的方法.对信号源内阻引起的误差进行了分析.给出了两种测量电容量的方案.  相似文献   

10.
本文根据对3种二阶节有源RC滤波器理论分析的结果作了机助分析和实验,比较三种滤波器国ω_O的偏差和Q的灵敏度及偏差可见,CAB滤波器性能最佳。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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