No abstract

Advances in near real-time rainstorm prediction using remote sensing have offered important opportunities for effective disaster management. However, this information is subject to several sources of systematic errors that need to be corrected. Temporal and spatial characteristics of both satellite and in-situ data can be combined to enhance the quality of storm estimates. In this study, we present a spatiotemporal object-based method to bias correct two sources of systematic error in satellites: displacement and volume. The method, Spatiotemporal Contiguous Object-based Rainfall Analysis for Bias Correction (ST-CORAbico), uses the spatiotemporal rainfall analysis ST-CORA incorporated with a multivariate kernel density storm segmentation for describing the main storm event characteristics (duration, spatial extension, volume, maximum intensity, centroid). Displacement and volume are corrected by adjusting the spatiotemporal structure and the intensity distribution, respectively. ST-CORAbico was applied to correct the early version of the Integrated Multi-satellite Retrievals for the Global Precipitation Mission (GPM-IMERG) over the Lower Mekong basin in Thailand during the monsoon season from 2014 to 2017. The performance of ST-CORABico is compared against the Distribution Transformation (DT) and Gamma Quantile Mapping (GQM) probabilistic methods. A total of 120 storm events identified over the study area were classified into short and long-lived storms by using a k-means cluster analysis method. Examples for both storm event types describe the error reduction due to location and magnitude by ST-CORAbico. The results showed that the displacement and magnitude correction made by ST-CORAbico considerably reduced RMSE and bias of GPM-IMERG. In both storm event types, this method showed a lower impact on the spatial correlation of the storm event. In comparison with DT and GQM, ST-CORAbico showed a superior performance, outperforming both approaches. This spatiotemporal bias correction method offers a new approach to enhance the accuracy of satellite-derived information for near real-time estimation of storm events.

The paper proposes an approach to design and implement temperature control base on digital PID controller in PLC. Hence it always guarantees the adaptive robust tracking stability of obtained closed loop systems in real time without using an additional penalty function in objective function as usual. The obtained control results by using this controller have confirmed its promising applicability in practice.

Effect of the weight proportion between epoxy resin modified by palm oil (EPO) and a biscycloaliphatic diepoxide (BCDE) on photoinitiated cationic crosslinking of the system containing EPO, BCDE, triarylsulfonium hexafluoroantimonate salts (TAS) as well as performance of formed coatings have been investigated. The change of TAS and functional groups of the system upon UV‐irradiation time was determined quantitatively by IR‐spectrometric analysis, using internal standard method. Formation of tridimensional polymer network in the coatings upon UV‐exposure was proved directly by evaluation of their gel fraction. It was demonstrated that epoxy group conversion and EPO/BCDE weight ratio relationship had optimal characteristic with the best consumptions of epoxy groups 5.94 and 6.13 mol/kg at 1.2 and 14.4 s of UV‐exposure, correspondingly, when EPO/BCDE weight ratio was 20/80. Augmentation of the EPO/BCDE ratio from 20/80 to 60/40 increased flexibility of UV‐cured coatings from 10 to 1 mm but decreased their gel fraction from 81 to 59 %; the relative hardness of the cured coatings diminished from 0.95 to 0.43 when the EPO/BCDE ratio varied from 10/80 to 40/60.