Review and comparative study of I-V characteristics of different memristor models with sinusoidal input

ABSTRACT

Memory-resistor (Memristor) has drawn considerable attention of the researchers in the last decade due to its remarkable properties. After the first concept of memristor, proposed by Leon Chua in 1971, almost no research work was conducted in this field for a long time. However, since the revolutionary discovery of the physical structure of memristor and its model of the HP lab in 2008, a tremendous amount of research work has been going on. Researchers are focusing on improving the models for the analysis of the memristor. Different researchers have come up with their model to improve the existing ones. These models can be linear, nonlinear or exponential. To overcome the boundary problem, many window functions have been proposed. Different models have their explanations of voltage-current relationship and state variable derivatives. This paper presents a detailed review and a comparative study of the existing memristor models based on their I-V characteristic curve. Original experimental I–V curve from the HP lab has been used as the reference for comparison.     

The relative effects of residual stresses and weld toe geometry on fatigue life of weldments

The weld toe is one of the most probable fatigue crack initiation sites in welded components. In this paper, the relative influences of residual stresses and weld toe geometry on the fatigue life of cruciform welds was studied. Fatigue strength of cruciform welds produced using Low Transformation Temperature (LTT) filler material has been compared to that of welds produced with a conventional filler material. LTT welds had higher fatigue strength than conventional welds. A moderate decrease in residual stress of about 15% at the 300 MPa stress level had the same effect on fatigue strength as increasing the weld toe radius by approximately 85% from 1.4 mm to 2.6 mm. It was concluded that residual stress had a relatively larger influence than the weld toe geometry on fatigue strength.     

Spinodal分解浅介

主要以经典理论,即二元合金spinodal分解的热力学判据 (a)2G/(a)C2<0为基础,简介spinodal分解的一般概念、理论和动力学.强调指出:spinodal分解的经典理论也面临由Binder等提出新概念的强烈挑战,即形核-长大机制与spinodal分解是连续变化的;以及Binder等思想的重要性.对spinodal一词的来源作简单的论述.     

塑料高频焊接技术

高频焊接是一种依靠极性塑料的介质滞后损耗产生内部发热的焊接方法。由于具有焊接速度快、焊缝强度高和外观质量优良等优点,该方法在医疗、包装、汽车行业得到了广泛的应用。本文论及塑料高频焊接技术。主要介绍了高频焊的原理、焊接过程、焊接设备、工艺参数、接头形式、焊接性、特点、应用和最新进展。     

区划调整和转型发展双重背景下上海市黄浦区规划策略探讨

经国务院批准,2011年5月20日,上海市撤销原黄浦区、卢湾区建制,建立新的黄浦区。此次区划调整使得新黄浦区开始跨入促进"两区融合,一体发展"的特殊阶段,同时新黄浦区又面临转型发展之大背景。因此,在分析了新黄浦区发展面临转型发展和区划调整双重背景基础之上,重点聚焦促进城区科学发展的整合、转型、创新三大关键词,深入明确两区融合发展的新战略,落实规划管理新重点,为上海市新黄浦未来发展提供思路。     

蓝相液晶光电特性研究

蓝相液晶由于其特有的扭曲双螺旋结构,具有快速响应特性与宏观上的光学各向同性。通过聚合物稳定的方法,可以提升其热稳定性,但是也导致了驱动性能下降,磁滞效应增强等问题。文章通过研究手性掺杂和聚合物网络对蓝相液晶材料体系的作用以及不同温度下的磁滞效应,探索蓝相液晶器件光电特性的影响因子,为改善蓝相液晶材料的光电特性提供理论上的支持。     

Fatigue behavior and life prediction of PI/SiO2 nanocomposite films

In this report, the fatigue behavior and lifetime of Polyimide/silica (PI/SiO₂) hybrid films are investigated. To evaluate the fatigue property of this class of hybrid films, the stress‐life cyclic experiments under tension–tension fatigue loading with 10 Hz of the frequency are performed, and the stress ratio is 0.1. Dynamic creep and cyclic softening/hardening are analyzed based on the change of hysteresis loops during the fatigue process. The structure‐property relations are discussed to further understand their phenomenon and deformation mechanisms. To predict the fatigue life of this class of hybrid films, a semiempirical model is proposed based on fatigue modulus concept. The simulated results are well agreeable with the testing values. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

T8Mn钢珠光体连续冷却转变动力学

用定量金相法Ｆｏｒｍａｓｔｏｒ－Ｄｉｇｉｔａｌ膨胀仪分别测得Ｔ８Ｍｎ钢以１℃／ｍｉｎ冷速下和不同冷速下的连续冷却动力学曲线。用线笥回归分析法得到动力学转变的数学模型。