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This paper explains the modelling and simulation of we modeled and simulate the power output of bifacial PV modules installed over different albedos using monofacial PV performance models (analytical and empirical). The analytical model and empirical models were evaluated using experimental data obtained from the testbed consisting of three bifacial PV arrays mounted in the same configuration but with different rear irradiance conditions: (1) backside covered by white plastic, (2) over normal albedo, and (3) over high albedo. The models use the measured effective solar irradiances and the PV module temperatures to simulate the power output in a healthy condition; they were adapted to bifacial modules by introducing the irradiance bifacial gain in the models’ equations. The results of the comparison showed that both models achieved good performance to simulate the instantaneous output of the PV arrays. Daily energy relative errors during sunny days were much less than overcast days, or about 1% for both models, excluding the shading effect. However, compared to the empirical model, the analytical model achieved better performances considering the bifaciality of the PV modules. In addition, the error for the entire monitored period (74 days during March, April, and May 2020) was less than 1.5% for the analytical model, including sunny and cloudy days; such high accuracy in the energy output forecast shows that the analytical model can accurately predict the generation of bifacial PV modules under different skies conditions.

The non-equilibrium Green function (NEGF) method is capable of nanodevice performance predictions including coherent and incoherent effects. To treat incoherent scattering, carrier generation and recombination is computationally very expensive. In this work, the numerically efficient Buttiker-probe model is expanded to cover recombination and generation effects in addition to various incoherent scattering processes. The capability of the new method to predict nanodevices is exemplified with quantum well III-N light-emitting diodes and anti-ambipolar 2D material hetero junctions.

Transition metal dichalcogenides (TMDCs) based 2D materials appear to very promising materials for tunnel field-effect transistors (TFETs). [1], [2]. The intrinsic subthreshold slope (SS) of these devices is determined by exponentially decaying band tail states/Urbach tails below conduction and valence band edges which places a lower bound on SS. Though there have been few recent studies on calculating and extracting band tails using simple models and qualitative analysis [3], [4], a rigorous study based on atomistic approach is still lacking.

As interconnects become smaller, their conductivity increases along with the parasitic effects in MOSFET technologies [1] Therefore, investigating how to model the scattering effects on the nanoscale is important to determine how to engineer interconnects toreduce those parasitic effects. In this work, a fully atomistic method is studied to model the electronic transport properties of copper thin films. For this purpose, a tight binding basis previously benchmarked against first principles calculations [2] is used todescribe surface roughness and grain boundary effects on comparablepper thin films with a thickness comparable to the values suggested by ITRS roadmap [3]. In contrast with traditional models, the results show that the tight binding method can quantify those scattering effects at low temperature without fitting any experimental parameters [4], [5].

As logic devices continue to downscale, interconnections are reaching the nanoscale where quantum effects are important. In this work we introduce a semi-empirical method to describe the resistance of copper interconnections of the sizes predicted by ITRS roadmap. The resistance calculated by our method was benchmarked against DFT for single grain boundaries. We describe a computationally efficient method that matches DFT benchmarks within a few percent. The 1000x speed up compared to DFT allows us to describe grain boundaries with a 30 nm channel length that are too large to be simulated by ab-initio methods. The electrical resistance of these grain boundaries has a probability density distribution as a function of the grain rotation angles. This approach allows us to quantitatively obtain the most likely resistance for each configuration.

Molybdenum disulfide (MoS 2 ) is a promising 2D material since it has a finite band gap, and its electronic band structure depends on the layer thickness. The tunability of the gate voltage on band alignment of different MoS 2 layers is analyzed. For this purpose, the multipurpose nanodevice simulation tool NEMO5 was altered by several new features: electronic bandstructure calculations in maximally localized Wannier function (MLWF) representation and self-consistent charge calculations with subatomic electrostatic resolution.

Nowadays, wavelet transform (WT) is widely used in the realm of signal denoising, has proven a high effectiveness in terms of time and quality concerning denoising methods. Despite there are several achievements denoising through wavelet thresholding methods, these do not disclose an optimal configuration. In this paper, we proposed a comparative performance analysis of several thresholding methods using WT; biological signals are denoised to obtain performance metrics. The efficiency of particular thresholding methods: rigrsure, sqtwolog, heursure and minimaxi using hard and soft thresholding are compared in the presence of low Gaussian noise also the effect of wavelet decomposition levels is analyzed. For wavelet decomposition, Haar wavelet is used. Experimental results show that by increasing decomposition levels likewise there was a denoising improvement in terms of root mean square error (RMSE) and correlation coefficient, however, from the fifth decomposition level RMSE and correlation coefficient slowly tends to get worse, also the threshold method rigrsure on soft thresholding improved RMSE of 1.77 to 1.03 and correlation coefficient of 99.32% to 99.71% while others techniques on both, soft and hard thresholding did not improve more than 1.1 in RMSE and 99.67% in correlation coefficient.

In this paper, we report a fast effective mass model for accurately calculating the bound states and optical transitions of self-assembled quantum dots. The model includes the atomistic strain effects, namely, the strain deformation of the band edges, and strain modification of the effective masses. The explicit inclusion of strain effects in the picture has significantly improved the effective mass model results. For strain calculations, we have found that atomistic strain depends solely on the aspect ratio of the quantum dot, and it has been calculated and reported here for a wide range of quantum dot aspect ratios. Following this sole dependence on the aspect ratio; The deformation theory has been used to include the strain deformation of the band edges. Density function theory has been used to study the effect of strain on the electron and hole effective masses. The proposed effective mass model have an accuracy that is close to full atomistic simulation but with no computational cost.