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This paper presents, tests and compares three earthing systems (TT, TN and IT) for Micro-Grid (MG) protection against various fault types during the connected mode. The main contribution of this work is including the models of all the micro sources which interfaced to the MG by power electronic inverters. Inverters in turns are provided with current limiters and this also included in the inverter models to exactly simulate the real situation in the MG during fault times. Results proved that the most suitable earthing system for MG protection during the connecting mode is the TN earthing system. That system leads to a suitable amount of fault current sufficient to activate over current protection relays. With using TN system, Touch voltages at the faulted bus and all other consumer’s buses are less than the safety limited value if current limiter is included with the transformer of the main grid which connects MG. For the two others earthing systems (TT and IT), fault current is small and nearly equal to the over load current which make over current protection relay can not differentiate between fault current and overload current. All models of micro sources, earthing systems, inverters, main grid and control schemes are built using Matlab(R)/Simulink(R) environment.

We devised new body shape silhouettes to more accurately reflect Japanese body sizes. Our aim was to assess the association between measured body mass index (BMI) and body size through self-selection of nine figure scales. This study was comprised of 4808 men and 1093 women aged 35–71 years. Subjects were asked to identify the silhouettes that most accurately represent their current body size. BMI was calculated from measured height and weight based on annual health checkups. Spearman’s correlation coefficients between silhouette ratings and BMI were 0.73 in men and 0.80 in women. Moreover, mean BMIs increased in value with increasing silhouette numbers in both genders (trend p < 0.01 for both). Simple linear regression models predicting BMI based on silhouette ratings showed a good fit, with silhouette self-selection statistically explaining 54.0% of BMI variance in men and 62.5% in women. Receiver operating curves showed that areas under the characteristics curves were higher than 0.8 for obesity and thinness in both genders. These findings suggest that our scale is a promising tool for examining body size and image among Japanese adults.