Validating a method of analysis goes through different steps, which aims at testing the normality of measurements distribution, estimating the uncertainty of the components of a measurement (i.e., accuracy and correc...Validating a method of analysis goes through different steps, which aims at testing the normality of measurements distribution, estimating the uncertainty of the components of a measurement (i.e., accuracy and correctness), and finally, define the control tests of non degradation of the method performances. This paper outlines the steps for validating a biological method of analysis. It involves the construction of an experimental design, a statistical model, and the preparation of an interne laboratory reference material (pilot vaccine). The latter is used to study the impact of deviation and variation factors, in order to, optimize the analytical method, to evaluate the bias (random error), and to calculate the uncertainty of measurement, and make the control charts. This method is applied in the titration of live viral vaccines of Gumboro disease on chicken's embryos fibroblasts. The experimental results show that potential influence factors related to the titration method had no significant influence on the obtained results. Taking into account these results, an operating mode has been elaborated. The finalized method proved to be faithful to standard deviation of repeatability and reproducibility of 0.21 and 0.22, respectively, with a confidence level of 95%. The calculated uncertainty of measurement is equal to 0.2, which represents the average error level of a titer. A homogeneous stock of interne laboratory reference vaccine (MRIL), with an average titer of 5.9 log DIT 50, was produced and the control chart set in away to provide the laboratory with an important tool of control and monitoring of the viral titers evolution in time, as well as, the mastery of the validated titration method performances.展开更多
Based on Hertz contact theory, contact area parameters between ball and raceway are calculated. Using the Creep theory of Cater and V-J theory, adhesive area and micro-slip area in the contact area are analyzed. It is...Based on Hertz contact theory, contact area parameters between ball and raceway are calculated. Using the Creep theory of Cater and V-J theory, adhesive area and micro-slip area in the contact area are analyzed. It is considered that micro-adhesion wear of micro convex body in the slip area is the main reason for accuracy degradation of a linear ball guide pair. And, the characteristics of the contact area between ball and raceway of slider are characterized using the fractal function. Fractal parameters are obtained using the least squares fitting double logarithmic graph structure function. Considering the lubrication condition between the ball and rail of slider, stress analysis is carried out on the adhesive area. A fractal-creep model of contact surfaces is established in the micro-slip region. The fractal parameters of a certain guide rail are measured, and the wear degradation process of linear rolling guide is simulated. Finally, the relationship between wear and relative tangential velocity, normal load and running mileage of linear ball guide is obtained.展开更多
文摘Validating a method of analysis goes through different steps, which aims at testing the normality of measurements distribution, estimating the uncertainty of the components of a measurement (i.e., accuracy and correctness), and finally, define the control tests of non degradation of the method performances. This paper outlines the steps for validating a biological method of analysis. It involves the construction of an experimental design, a statistical model, and the preparation of an interne laboratory reference material (pilot vaccine). The latter is used to study the impact of deviation and variation factors, in order to, optimize the analytical method, to evaluate the bias (random error), and to calculate the uncertainty of measurement, and make the control charts. This method is applied in the titration of live viral vaccines of Gumboro disease on chicken's embryos fibroblasts. The experimental results show that potential influence factors related to the titration method had no significant influence on the obtained results. Taking into account these results, an operating mode has been elaborated. The finalized method proved to be faithful to standard deviation of repeatability and reproducibility of 0.21 and 0.22, respectively, with a confidence level of 95%. The calculated uncertainty of measurement is equal to 0.2, which represents the average error level of a titer. A homogeneous stock of interne laboratory reference vaccine (MRIL), with an average titer of 5.9 log DIT 50, was produced and the control chart set in away to provide the laboratory with an important tool of control and monitoring of the viral titers evolution in time, as well as, the mastery of the validated titration method performances.
基金Supported by the National Natural Science Foundation of China(No.51505012,51575014)the Natural Science Foundation of Beijing(No.3154029,KZ201410005010)+1 种基金the Important National Science&Technology Specific Projects of China(No.2012ZX04010021-001-004)Beijing Postdoctoral Research Foundation(No.2015XX-13)
文摘Based on Hertz contact theory, contact area parameters between ball and raceway are calculated. Using the Creep theory of Cater and V-J theory, adhesive area and micro-slip area in the contact area are analyzed. It is considered that micro-adhesion wear of micro convex body in the slip area is the main reason for accuracy degradation of a linear ball guide pair. And, the characteristics of the contact area between ball and raceway of slider are characterized using the fractal function. Fractal parameters are obtained using the least squares fitting double logarithmic graph structure function. Considering the lubrication condition between the ball and rail of slider, stress analysis is carried out on the adhesive area. A fractal-creep model of contact surfaces is established in the micro-slip region. The fractal parameters of a certain guide rail are measured, and the wear degradation process of linear rolling guide is simulated. Finally, the relationship between wear and relative tangential velocity, normal load and running mileage of linear ball guide is obtained.