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A three-step numerical procedure has been developed, which facilitatesthe conversion of NDP energy spectra into lithium concentrationdepth profiles for thin-film Li-ion batteries. The procedureis based on Monte Carlo modeling of the energy loss of chargedparticles (ions) in the solid media, using the publically availableSRIM/TRIM software. For the energy-to-depth conversion, the batterystack has been split into finite volume elements. Each finite volumeelement becomes a source of ions according to the employednuclear reaction. Ions loos energy when they move across the batterystack towards the detector. The as-obtained simulated spectrahave been compared with the experimentally measured spectra. Thethicknesses of the battery stack layers were estimated by minimizingthe deviation between the simulated and measured spectra. Subsequently,a relation between the average energy of detected ions andthe depth of the corresponding finite volume element, yielding a calibrationfunction, was used to relate that particular part of the spectrawith the depth of its source. At the final stage, a Bayesian estimatorwas used to find the distribution of lithium at a particular depth. Thedeveloped procedure was applied to a practically relevant case studyof Si immobilization in the LPO electrolyte of all-solid-state thin-filmbatteries. It is shown that the lithium immobilization process in theLPO electrolyte is responsible for the battery degradation process.

Cheating is a serious problem in many countries. The cheater gets high- er marks than deserved, thus reducing the efficiency of a country's educational system. In this study, the authors did not ask if and how often the student had cheated, but rather what the student's opinion was about a cheating situation. They investigated whether attitudes differ among students in Russia, the Nether- lands, Israel, and the United States and conclude that attitudes toward cheating differ considerably between these countries. They offer various explanations of this phenomenon. In addition, they find that the student's attitude toward cheat- ing depends on the student's educational level (high school, undergraduate, post- graduate). Finally, they show that the data from the sample can be aggregated in a natural and elegant way, and they suggest a tolerance-of-cheating index for each country.

This article describes a time series forecast method based on the principal component analysis applied to the data matrix derived from the initial time series.