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DC voltage detection of sub-modules is very important for the stability of cascaded multilevel converters. Operation and maintenance personnel need a detection algorithm to supplement the uncertainty and risk caused by the traditional redundancy scheme. This paper presented a DC voltage indirect estimation method based on current transformer. The method uses the AC side current value, as well as the sub-module equivalent circuit model and switching state to estimate the DC voltage of the sub-module of the cascade system. The estimation models are established and can be used to the sub-modules of three topologies, i.e., half-bridge, H bridge topology and clamp double sub-module. Simulation and experimental systems are built to testify the proposed method. The results showed that, when N = 3 or 12, the indirect detection model based on AC current met the requirements of detection accuracy within 1% under different calculation steps, and the sampling error had little influence on it. The indirect estimation method could reduce the use of DC transformers and improve equipment reliability and maintainability. [ABSTRACT FROM AUTHOR]

The current study concentrates on the issue of income related inequality in obesity for the case of European Union, an association, which has not been thoroughly examined in the literature. Ten European countries for a period of 4 consecutive years (1998–2001) are under consideration, with the information deriving from the “European Community Household Panel” (ECHP) dataset. In order to elaborate on the above association, the concentration index was selected as a means for measuring quantitatively the degree of inequality. Furthermore, an alternative method was introduced, known as the “indirect standardization method,” so as to examine if the observed level of inequality was over-reported. Treating the European Union as a whole, income inequality in obesity appears to be a burden for the less affluent. Investigation of each country separately reveals that inequality is of most importance for the female population, and especially for the middle-aged one, while no clear association was found for the males. Furthermore, negligence to adjust the models for the education level and the employment status could lead to an over-estimation of the inequality in obesity. Our primary results attest to the existing literature, showing that a BMI with a value greater than 30 is most likely to be an encumbrance for those of low socioeconomic profiles. However, the extent of inequality in the European Union is found to be low. Effective preventive policies should address the low socioeconomic status female population in Europe, and special attention should be given to the middle-aged. [ABSTRACT FROM AUTHOR]

From a quantitative point of view, the foreign and immigrant presence in the labor market is well known, thanks to the many official statistical reports. On the other hand, we do not know much about the inflows and outflows which affect the active foreign and immigrant population. The precise objective of this paper is to address that gap in our knowledge. By means of several hypotheses, if we accept an obvious lack of precision, we can approximate the yearly number of foreign entries into the French labor market by establishing an indirect method of estimation through drawing upon and developing information relative, on one hand to the foreign presence in the labour market and, on the other, to the flow of legal foreign nationals’ entries within the scope of permanent immigration. However, since the free circulation agreement between EU countries prevents us from being able to determine the migratory population movement of native Europeans precisely, the indirect measure of the yearly number of new foreign workers can only encompass those from countries outside of this agreement. Despite this limitation, the numerical application from 2007 to 2009 enables us to considerably add to the information needed for a rough estimation of foreigners coming into France.Consequently, we are able to establish that about 130,000 foreign natives from non-EU countries arrived in France as permanent immigrants. Among them, one in ten already had an employment contract in France, and half entered the labour market in the following year. If we add inactive foreigners present in France for several years who gained access to the labour market for the first time, the yearly flow of new active native foreigners from non-EU countries between 2007 and 2009 rises to about 100,000 people—the greatest increase in 20 years.