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991.
《Physics letters. A》2014,378(22-23):1588-1592
We examine the possibility of obtaining Set–Reset latch logical operation in a symmetric bistable system subjected to OU noise. Three major results are presented. First, we prove the Set–Reset latch logical operation can be obtained driven by OU noise. Second, while increasing the correlation time, the optimal noise band shifts to higher level and becomes wider. Meanwhile, peak performance degrades from 100% accuracy, but the system can still perform reliable logical operation. Third, at fixed noise intensity, the success probability evolves non-monotonically as correlation time increases. The study might provide development of the new paradigm of memory device. 相似文献
992.
K. Velmanirajan K. Anuradha A. Syed Abu Thaheer R. Ponalagusamy R. Narayanasamy 《Applied Mathematical Modelling》2014
This paper investigates the formability and forming limit curve of aluminium alloy sheet of grade Al 1350 with respect to annealing temperature and strain conditions through statistical approach. The uncertainty of forming limit curve (FLC) due to anisotropy parameter and strain hardening exponent have also been taken into consideration. The plastic instability criteria and its relevant equations given by Hill have been used to construct the theoretical FLC which is compared with experimental FLC. The stochastic modeling has been made on the statistical evaluation of the FLC with a high confidence level. First Order Reliability Method (FORM) and Monte-Carlo simulation (MCS) methods have been used to compare the probability of the data points determining FLC by considering normal distribution of material properties. 相似文献
993.
Gold nanoparticles,owing to their unique physicochemical and optical properties,well-established synthetic methods and easy modifications,have been widely used in biomedical science.Therefore,for their safe and efficient applications,much attention has been given to the toxicological evaluations of gold nanoparticles in biological systems.A large number of studies focusing on this problem have been carried out during the past years.However,the researches on gold nanoparticles toxicity still remain fragmentary and even contradictory with each other.This may be caused by the variety in experimental conditions.In this review,we aim to provide a better understanding about the in vitro and in vivo toxicity of gold nanoparticles by reviewing and describing the up to date literatures related to this problem and we mainly focused on these properties such as the particle size and shape,the surface charge and modification.Besides,we also summarized the adverse effect of gold nanoparticles on immune systems and analyzed the origin of the toxicity. 相似文献
994.
Stanislav Nagy Irène Gijbels Daniel Hlubinka 《Journal of computational and graphical statistics》2017,26(4):883-893
A major drawback of many established depth functionals is their ineffectiveness in identifying functions outlying merely in shape. Herein, a simple modification of functional depth is proposed to provide a remedy for this difficulty. The modification is versatile, widely applicable, and introduced without imposing any assumptions on the data, such as differentiability. It is shown that many favorable attributes of the original depths for functions, including consistency properties, remain preserved for the modified depths. The powerfulness of the new approach is demonstrated on a number of examples for which the known depths fail to identify the outlying functions. Supplementary material for this article is available online. 相似文献
995.
Most condoms, especially those purchased by international aid agencies, are packed in square aluminium foil packs. The alternative rectangular packs use less packing material, and are more compact to ship and store. In this article, we describe a trial where condoms in square packs and in simulated rectangular packs were tested for physical properties after oven-conditioning for 3 months at 50 °C. We concluded that some products' inflation properties were unaffected by the pack shape. All products' tensile properties were adversely affected by a rectangular pack when a ring sample was used, but when more conventional dumbbell samples were used, the effect was quite small. 相似文献
996.
Low-Energy Electron Attachment to Serine Conformers: Shape Resonances and Dissociation Dynamics
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Shape resonances of electron-molecule system formed in the low-energy electron attachment to four low-lying conformers of serine (serine 1, serine 2, serine 3, and serine 4) in gas phase are investigated using the quantum scattering method with the non-empirical model potentials in single-center expansion. In the attachment energy range of 0-10 eV, three shape resonances for serine 1, serine 2, and serine 4 and four shape resonances for serine 3 are predicted. The one-dimensional potential energy curves of the temporary negative ions of electron-serine are calculated to explore the correlations between the shape resonance and the bond cleavage. The bond-cleavage selectivity of the different resonant states for a certain conformer is demonstrated, and the recent experimental results about the dissociative electron attachment to serine are interpreted on the basis of present calculations. 相似文献
997.
Marcelo A. Savi Pedro M. C. L. Pacheco Arthur M. B. Braga 《International Journal of Non》2002,37(8):733-1395
The study of the structural response of two-bar trusses may be very helpful to understand some of the main stability characteristics of framed structures, as well as of flat arches and of many other physical phenomena associated with bifurcation buckling. This article is concerned with the dynamic response of a shape memory two-bar truss, which is an interesting example of a structural system that exhibits both kinematic and constitutive non-linearities. A polynomial constitutive model is assumed to describe the behavior of the shape memory bars. Free and forced responses are investigated. Numerical simulations show that the system can easily reach a chaotic response. 相似文献
998.
M. Panico 《Journal of the mechanics and physics of solids》2007,55(11):2491-2511
In this work, we propose a macroscopic phenomenological model that is based on the classical framework of thermodynamics of irreversible processes and accounts for the effect of multiaxial stress states and non-proportional loading histories. The model is able to account for the evolution of both twinned and detwinned martensite. Moreover, reorientation of the product phase according to loading direction is specifically accounted for. Towards this purpose the inelastic strain is split into two contributions deriving, respectively, from creation of detwinned martensite and reorientation of previously existing martensite variants. Computational tests demonstrate the ability of the model to simulate the main aspects of the shape memory response in a one-dimensional setting and some of the features that have been experimentally found in the case of multiaxial non-proportional loading histories. Experimental non-proportional loading paths have also been simulated and a good qualitative agreement between numerical and experimental response is observed. 相似文献
999.
S. Stupkiewicz H. Petryk 《Journal of the mechanics and physics of solids》2002,50(11):2303-2331
This paper is concerned with micromechanical modelling of stress-induced martensitic transformations in crystalline solids, with the focus on distinct elastic anisotropy of the phases and the associated redistribution of internal stresses. Micro-macro transition in stresses and strains is analysed for a laminated microstructure of austenite and martensite phases. Propagation of a phase transformation front is governed by a time-independent thermodynamic criterion. Plasticity-like macroscopic constitutive rate equations are derived in which the transformed volume fraction is incrementally related to the overall strain or stress. As an application, numerical simulations are performed for cubic β1 (austenite) to orthorhombic γ1′ (martensite) phase transformation in a single crystal of Cu-Al-Ni shape memory alloy. The pseudoelasticity effect in tension and compression is investigated along with the corresponding evolution of internal stresses and microstructure. 相似文献
1000.
Marc Defossez 《Mechanics Research Communications》2003,30(4):311
This paper demonstrates that symmetric tensegrity structures can have a shape memory effect. It has been found that the ratio of potential energy between two equilibrium states can vary considerably when the original length of the elastic elements is changed. It is then suggested that those structures may be used as shape memory actuators. 相似文献