New Monitoring Strategy for the Quality Control in the Processing Practice of Scutellariae Radix

Background: Scutellariae Radix (Huangqin) is commonly processed into 3 products for different clinical applications. However, a simple analytical method for quality control has rarely been reported to quickly estimate the degree of processing Huangqin or distinguish differently processed products or unqualified Huangqin products. Objective: To study a new strategy for quality control in the processing practice of Huangqin. Methods: Seven kinds of flavonoids that mainly exist in Huangqin were determined by HPLC-DAD. Chromatographic fingerprints were established to study the variation and discipline of the 3 processed products of Huangqin. PCA and OPLS-DA were used to classify differently processed products of Huangqin. Results: The results showed that baicalin and wogonoside were the main components in the crude and the alcohol Huangqin herb while baicalein and wogonin mainly existed in carbonized Huangqin. The results of mathematical statistics revealed that the processing techniques can make the quality of medicinal materials more uniform. Conclusion: This multivariate monitoring strategy is suitable for quality control in the processing of Huangqin.

3D modeling system of seismoacoustic monitoring results at the Nikolaevskoye field

The complexity of solving the problem of preventing natural and man-made disasters during intensive nature management is associated with the multifactorial nature of the conditions and causes of catastrophic events, significant variations in the properties and state of geospheres, and the lack of reliable criteria and precursors of dangerous dynamic phenomena. The modern scientific approach to solving this problem consists in modeling processes that allow to adequately describe the state of changing natural and technical systems with subsequent verification of the results of theoretical research by instrumental methods. An even greater effect is brought by the combined use of natural and theoretical methods, united by a common ideology and maximally adapted to the conditions of the problem being solved, providing continuous multivariate monitoring of geophysical fields and processes in the geospheres. In this regard, it seems very urgent to set up research work aimed at the development of scientific and methodological foundations and technical means for assessing and monitoring hazardous geomechanical processes to reduce the risk of man-made disasters during the development of mineral deposits.

An Aging-Degree Evaluation Method for IGBT Bond Wire with Online Multivariate Monitoring

The aging fracture of bonding wire is one of the main reasons for failure of insulated gate bipolar transistor (IGBT). This paper proposes an online monitoring method for IGBT bonding wire aging that does not interfere with the normal operation of the IGBT module. A quantitative analysis of aging degree was first performed, and the results of multivariate and univariate monitoring were compared. Based on the relationship between the monitoring parameters and the aging of the IGBT bonding wire, gradual damage of the IGBT bond wire was implemented to simulate aging failure and obtain the aging data. Moreover, the change of junction temperature was considered to regulate monitoring parameters. Then, the aging degree was evaluated by an artificial neural network (ANN) algorithm. The experimental results showed the effectiveness of the proposed method.