Abstract The cumulative installed capacity of photovoltaics has passed 1 TW, which about two-thirds were only in the past five years. Many these new installations incorporate novel module and cell designs that have not yet been subjected to long-term in-field characterization. Indoor accelerated stress testing historically a valuable methodology identify fault mechanisms, estimate degradation r...

Forward bias current–voltage characteristics (JD – V) were studied for both p – i – n ~superstrate! and n – i – p ~substrate! (a-SiC:H p)/(a-Si:H i) solar-cell structures having different p/i interface layers and different thickness i-layers. Contributions of the p/i interfaces to the JD – V characteristics were separated, and the dependence on the thickness of the i-layers was established. Equ...

Let G be a simple graph with vertex set V(G) {v1,v2 ,...vn} . For every vertex i v , ( ) i  v represents the degree of vertex i v . The h-th order of Randić index, h R is defined as the sum of terms 1 2 1 1 ( ), ( )... ( ) i i ih  v  v  v  over all paths of length h contained (as sub graphs) in G . In this paper , some bounds for higher Randić index and a method for computing the higher R...

The vortex glass transition in the presence of columnar defects is studied by Monte Carlo simulations of a vortex loop model, suggested by the analogy to the T = 0 superconductor-insulator transition for dirty bosons in (2+1)D. From finite-size scaling analysis of the I-V characteristic we find two dynamical exponents describing the non-equilibrium behavior. We obtain z⊥ = 6±0.5 and z‖ = 4 ± 0....

The performance of carbon nanotube-based transistor is analyzed. The effect of geometrical parameters on the device performance is investigated as d tunnel. We have studied the influence of the material parameters, such as the height of the SB (ΦSB), and some other physical parameters like the nanotube chirality, the gate oxide thickness and the gate oxide dielectric permittivity Our results sh...

In 1975, Julliere proposed a simple model for tunneling between two ferromagnetic metals, assuming that the spin is conserved in the tunneling process and that the tunneling current is proportional to the density of states of each spin at the ferromagnetic electrodes. A magnetoresistance ~MR! effect then appears when one compares the resistance for cases in which the magnetization of the electr...

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