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91.
92.
Environmental Impacts on Spiking Properties in Hodgkin-Huxley Neuron with Direct Current Stimulus 下载免费PDF全文
Based on the well accepted Hodgkin-Huxley neuron model, the neuronal intrinsic excitability is studied when the neuron is subject to varying environmental temperatures, the typical impact for its regulating ways. With computer simulation, it is found that altering environmental temperature can improve or inhibit the neuronal intrinsic excitability so as to influence the neuronal spiking properties. The impacts from environmental factors can be understood that,the neuronal spiking threshold is essentially influenced by the fluctuations in the environment. With the environmental temperature varying, burst spiking is realized for the neuronal membrane voltage because of the environment-dependent spiking threshold. This burst induced by changes in spiking threshold is different from that excited by input currents or other stimulus. 相似文献
93.
We thank all the discussants for their interesting and stimulating contributions. They have touched various aspects that have not been considered by the original articles. 相似文献
94.
With a 45 nm process technique, the shrinking silicon feature size brings in a high-k/metal gate which significantly exacerbates the positive bias temperature instability (PBTI) and time-dependent dielectric breakdown (TDDB) effects of a NMOS transistor. However, previous works presented delay models to characterize the PBTI or TDDB individually. This paper demonstrates that the delay caused by the joint effects of PBTI and TDDB widely differs from the cumulated result of the delay caused by the PBTI and TDDB, respectively, with the experiments on an inverter chain. This paper proposes a hybrid aging delay model comprising both the PBTI and TDDB effects by analyzing the relationship between the aging propagation delay and the inherent delay of the gate. Experimental results on the logic gates under 45 nm, 32 nm, 22 nm, and 16 nm CMOS technologies show that the maximum error between the proposed model and the actual value is less than 2.5%, meanwhile the average error is about 1.5%. 相似文献
95.
段谟意 《智能计算机与应用》2015,(2):25-27
为了解决无线网络信号在传输过程中由于受到其他信号的干扰,导致接收端接收的信号与原始信号相比存在误差的问题,本文在利用数据关联和卡尔曼滤波对信号进行融合的基础上,提出了一种新的信号状态融合方法(signal fusion based on wavelet transform and date association,SFTD),该方法利用FARIMA(p,d,q)模型和数据关联来建立一种新的信号融合算法。通过仿真实验研究了信号发送速率与干扰信号功率之间的关系,仿真结果说明,SFTD算法比FSWC算法具有更好的信号状态融合准确性;并且发送速率、功率对融合信号也产生较大影响。 相似文献
96.
昌吉电视台2014年完成了4+2讯道新闻转播车的升级改造,详细介绍转播车系统的微波系统架构、新技术应用和无线传输技术方案,介绍该系统的优势所在,改造后进一步提高了系统在昌吉州应急突发事件等新闻转播中的应用能力。 相似文献
97.
Yong Sun Bo-Qiao Fu Ming-Wu Ding 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1437-1443
The isothiocyanates 2, obtained from aza-Wittig reactions of vinyliminophosphoranes 1 with CS 2 , reacted with hydrazine to give 3-amino-2-thioxo-4-imidazolidinones 4. One-pot reactions of 4, aromatic isocyanates, Ph 3 P, C 2 Cl 6 , and Et 3 N generated imidazo[2,1-b]-1,3,4-thiadiazol-5(6H)-ones 7. Compound 7 exhibited good fungicidal activities, especially against Sclerotinia sclerotiorum de Bary and Botrytis Cinerea Pers. 相似文献
98.
Le Wang Yong Ye Zhiyu Ju Shangbin Zhong Yufen Zhao 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1958-1963
A modified method for preparing large-scale quantities of pure hexachlorocyclophosphazene (N3P3Cl6) and octachlorocyclotetraphosphazene (N4P4Cl8), phosphorus pentachloride with ammonium chloride, in the presence of zinc chloride, has been developed. The time of the reaction and the quantities of the catalyst are also studied. It is found that the optimum reaction time is 1.5 h and by-products are remarkably reduced by addition of 10% zinc chloride. As indicated by the 31 P NMR spectra, the synthesis and separation of cyclophosphazenes can be accomplished in moderate yield of tetramer (39%) and good yield of trimer (83%). 相似文献
99.
100.
Yunyun Shi Lina Shao Jinghui Yang Ting Huang Yonghong Wang Nan Zhang Yong Wang 《先进技术聚合物》2013,24(1):42-50
In this work, a novel nucleating agent (NA) based on substituted‐aryl phosphate salts was introduced into poly(L‐Lactide) (PLLA). The nonisothermal and isothermal crystallization behaviors of nucleated PLLA samples were investigated through differential scanning calorimetry (DSC), wide angle X‐ray diffraction, and polarized optical microscope (POM). Furthermore, the effect of annealing treatment on the cold crystallization behaviors of nucleated samples was also investigated. The results show that the crystallization of PLLA, whether for the melt crystallization (including nonisothermal and isothermal crystallization process) or for the cold crystallization (including the cold crystallization occurring during the DSC heating process and during the annealing process), is greatly dependent upon the content of NA. At relatively lower NA content (≤0.1 wt%), the nucleation effect of NA is inconspicuous, however, at higher NA content (≥0.2 wt%), it exhibits great nucleation effect for the crystallization of PLLA. Further results show that the double endothermic peak of PLLA depends on the temperature applied for the crystallization. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献