Mechanical Characterization of Armchair and Zigzag Single-walled Carbon Nanotube

The stress-strain and Young’s modulus values of single-walled carbon nanotubes SWCNTs are modeled through linear finite element simulations and Matlab codes, in this study. Cylindrical zigzag and armchair single-walled are established as carbon nanostructures. An individual carbon nanotube (CNT) is simulated as a frame-like structure and the primary bonds between two nearest-neighboring carbon atoms are treated as 3D beam elements. The stiffness and the stress-strain curved of the SWCNTs are investigated. The effect domination of the nanotube diameter of the CNTs on Young’s modulus is studied. The simulation results acquired in this study are in good agreement with the experimental results

Circularly polarized transmitarray antenna design using meander line polarizer for ku-band applications

In this paper, a circularly polarized Transmitarray antenna design for the Ku-band frequency range is presented. The transmitarray antenna with 121 elements is designed using a four-layer double square ring with a center patch unit cell. The Unit cell parametric analysis shows a high transmission coefficient magnitude of -1.26 dBi and a wide phase range of 256 degrees. A meander line polarizer is designed at 12GHz to convert the polarization from linear to circular. This meander line polarizer is placed in front of the horn antenna as a superstrate layer. The final measurement results show a high gain circular polarized TA antenna with a maximum gain of 20.17dBic and a value of 1.89 for the axial ratio is achieved at 11.2 GHz. The 1dB antenna gain and 3-dB axial ratio bandwidth are calculated as 0.65GHz and 1.07GHz, respectively. The proposed design offers a low profile and less complex structure, making it suitable for long-range communication systems, especially in Ku band applicati

Development aid and international migration to Italy: Does aid reduce irregular flows?

In recent years, donors have claimed to tackle the root causes of migration from low‐income countries using aid. While others have studied the effects of aid on regular migration, we test whether aid deters irregular migration to Italy using two innovative dependent variables: asylum applications and apprehensions at border. For asylum applications, the largest significant effect size implies we should expect one extra application for an additional $162,000 in bilateral aid. For border crossings, the only significant effect implies the marginal cost in bilateral aid is$1.8 million per deterred migrant. The conclusion that effect sizes are small is robust to different types of aid, measures of migration and various controls. We find robust evidence that irregular migration flows are significantly affected by conflict, poverty, and the pre‐existing stocks from that country. Comparing our results to the existing aid‐migration literature, we find similar effect sizes. The cost per deterred (regular) migrant is in the range $4‐7 million. Statistically significant estimates for the effect of aid on regular migration are only found for sub‐samples or specific specifications. In short, aid does not deter regular or irregular migration, so should be used for other purposes

Libya and Europe: imperialism, crisis and migration

This article examines the recent dynamics of European imperialism in Libya in the light of Marx’s theory of the global reserve army of labour. It analyses the limited advance of Western imperialism in Libya in the decade before the 2011 uprisings, the interactions between local, regional and international forces during and after the North Atlantic Treaty Organization (NATO) intervention, and, finally, the evolving migratory patterns from Libya. In this light, the instability along the southern and eastern Mediterranean coastline – a product of the uprisings and the forms of political reactions they unleashed – is simultaneously a security threat and a channel of migratory movements to European capitalism

A nonlinear impulsive Intergro-differential system with infinite memory

In the present paper, we investigate the existence and uniqueness of periodic solution of a nonlinearimpulsive first order Integro-Differential system by innovatively applying the method of periodicsuccessive approximations of Samoilenko.A.M. [5]2000 AMS Classification Number: - 45J05, 34K05, 45L05, 47G20