Method of kurtosis in estimating the measurement uncertainty during calibration of the electrical resistance measures using a potentiometer

Calibration of electrical resistance measures is considered by the indirect method, which is realized through measuring the voltage drop across the series-connected reference and calibrated resistors. The biases of the estimates of the measurand and the combined standard uncertainty due to the nonlinearity of the measurement model were calculated. The distribution laws of the input quantities in the calculation of the expanded uncertainty were taken into account by the kurtosis method. An example of measurement uncertainty evaluating during calibration of single-size electrical resistance measure R331 with a nominal resistance of 1000 Ω by comparing its value using a potentiometer R345 with the value of the calibrated reference standard is considered. Estimates of the measurand and its standard and expanded uncertainties obtained using the proposed method showed good agreement with the estimates obtained using the Monte Carlo method.

Collapse-Resistance Measure for the Bottom Frame Structure under Earthquake

The bottom frame structure, with serious earthquake damage, occupies a large proportion in the houses collapsed in earthquakes. However, because it is economic and practical, it is still widely used. Based on the understanding of the seismic performance of bottom frame structure, this paper determines to study seismic measures of the bottom frame structure. The current seismic measures can be divided into two major categories: strengthening key components and avoiding key components, therefore this paper adopts the method of strengthening parts which are easy to collapse for reinforcement, under the premise of meeting the stiffness ratio between reasonable layers, adds wing wall to improve the capacity of resisting collapse of the structure and pinpoints the efficiency of adding wing wall in the capacity of resisting collapse through quantitative analysis. Although there are differences in the improvement of the capacity of resisting collapse under different seismic waves, adding wing walls reasonably can greatly improver the anti-collapse capacity of the structure..

Balanced Ventilation Principle in the Application of Shigetai Coal Mine Ventilation System Optimization

In order to reduce Shigetai coal mine ventilation resistance of mine ventilation system, using balanced ventilation principle Shigetai coal mine ventilation resistance of mine ventilation system was analysed and balanced, and the balanced ventilation resistance measure mine ventilation resistance in 2014-2015 simulation calculation. Results suggest that balanced ventilation measures implemented in mine ventilation resistance, coal mine ventilation resistance in the next two years not only with increased ventilation line length increases, but lower. Visible, balanced ventilation of mine has better technical and economic results are obvious, merits promotion.