Search results for "experimental data"
showing 10 items of 137 documents
Photoconductivity and photovoltaic effect in indium selenide
1983
Transport and phototransport properties of crystalline indium monoselenide (InSe) doped with a variety of elements are reported. Measured mobilities, lifetimes, and effective diffusion lengths of photoexcited carriers are used to interpret electrical and photovoltaic properties of several different structures. These include p‐n junctions, bismuth/p‐type InSe, platinum/n‐type InSe, and indium tin oxyde (ITO)/p‐type InSe. External solar efficiencies of the best devices are between 5% and 6%. The influence on the efficiency of the various parameters is evaluated, and ways of improvement are discussed.
Assessment of a New Analytical Expression for the Maximum-Power Point Voltage with Series Resistance
2021
This work compares a recently developed analytical expression for the maximum-power point voltage with experimental data, to test its usability for crystalline silicon solar cells. The experimental data covers measurements from 18 multicrystalline silicon solar cells with different bulk resistivities and cell architectures. We show that the expression is able to predict the maximum power obtainable by the measured cells with relative discrepancies below 1%. Additionally, we compare the accuracy of this new expression with two already existing models.
Robust model calibration using determinist and stochastic performance metrics
2016
International audience; The aeronautics industry has benefited from the use of numerical models to supplement or replace the costly design-build-test paradigm. These models are often calibrated using experimental data to obtain optimal fidelity-to-data but compensating effects between calibration parameters can complicate the model selection process due to the non-uniqueness of the solution. One way to reduce this ambiguity is to include a robustness requirement to the selection criteria. In this study, the info-gap decision theory is used to represent the lack of knowledge resulting from compensating effects and a robustness analysis is performed to investigate the impact of uncertainty on…
Neural Network Techniques for Metal Forming Design
1993
Neural networks are computing structures able to predict the behaviour of a system on the basis of the knowledge of facts; main characteristic of a network is the capability to find a rule in a very complex environment. In the paper a neural network, based on the results of FEM simulations, is utilized to predict the occurrence of defects in a forward extrusion metal forming process. In particular a three layers neural network, relating the operative parameters with the failure or the success of the working process, has been used and the back-propagation algorithm has been employed to train the network. Few experimental data were enough to train the neural network allowing to achieve better…
Calculation of phase diagrams for models of metallic alloys
2007
We briefly review a longstanding problem of metallurgy and statistical physics, namely, the prediction of phase diagrams of binary alloys from simple model assumptions on the atomic interactions, such as Ising-type models. Various methods of statistical mechanics which have been applied to this problem are introduced and compared to each other, such as the cluster-variation method and Monte-Carlo simulation. The merits as well as the limitations of these methods are discussed, emphasizing examples of fcc and bcc lattices which are potentially relevant for the problem of short-range order and long-range order in metallic alloys such as Cu−Au, Ni−Cr, and Fe−Al.A brief comparison with correspo…
Influence of data treatment on the shape of 2H NMR T1 curves
1993
A new interpretation of 2H T1 data of glass-forming systems in the range of the range of the caloric glass transition temperature has been proposed. It is shown that with the traditional treatment of the data the timescale of structural relaxation has an influence on the observed spin-lattice relaxation times. Avoiding this problem with a different treatment of the experimental data, it is possible to compare the 2H T1 data directly with corresponding 1H data.
In-beam and decay spectroscopy of transfermium nuclei
2008
Abstract In recent years the body of experimental data on nuclei with masses A ≃ 250 has increased dramatically. Nuclei that had been out of reach for experimental studies have now become available for study through a variety of approaches, both with in-beam spectroscopic methods and through spectroscopy following the decay of isomeric states or alpha decays at the focal plane of powerful separators. This article aims to collect the currently available experimental data on nuclei between Cm ( Z = 96 ) and Db ( Z = 105 ) . The review of this data builds on the evaluations in the literature and focusses on those datasets obtained most recently.
Nuclear data activities at the n_TOF facility at CERN
2016
International audience; Nuclear data in general, and neutron-induced reaction cross sections in particular, are important for a wide variety of research fields. They play a key role in the safety and criticality assessment of nuclear technology, not only for existing power reactors but also for radiation dosimetry, medical applications, the transmutation of nuclear waste, accelerator-driven systems, fuel cycle investigations and future reactor systems as in Generation IV. Applications of nuclear data are also related to research fields as the study of nuclear level densities and stellar nucleosynthesis. Simulations and calculations of nuclear technology applications largely rely on evaluate…
Electrical and photovoltaic properties of indium‐tin‐oxide/p‐InSe/Au solar cells
1987
Conditions for efficiency improvement and optimization in indium‐tin‐oxide/p‐indium‐selenide solar cells are discussed in this paper. This aim is achieved by using low‐resistivity p‐indium‐selenide and by incorporating a back‐surface‐field contact. This contact is insured by a p‐indium selenide/gold barrier whose rectifying behavior is explained through the complex impurity structure of p‐indium‐selenide. Electrical and photovoltaic properties of the cells are also reported. The efficiency parameters under AM1 simulated conditions have been improved up to 32 mA/cm2 for the short‐circuit current density, 0.58 V for the open‐circuit voltage, and 0.63 for the filling factor. As a result, solar…
Quest for precision in hadronic cross sections at low energy: Monte Carlo tools vs. experimental data
2010
We present the achievements of the last years of the experimental and theoretical groups working on hadronic cross section measurements at the low-energy e (+) e (-) colliders in Beijing, Frascati, Ithaca, Novosibirsk, Stanford and Tsukuba and on tau decays. We sketch the prospects in these fields for the years to come. We emphasise the status and the precision of the Monte Carlo generators used to analyse the hadronic cross section measurements obtained as well with energy scans as with radiative return, to determine luminosities and tau decays. The radiative corrections fully or approximately implemented in the various codes and the contribution of the vacuum polarisation are discussed.