SCANNING AND PROCESSING COMPUTER SYSTEM FOR GRAPHIC INFORMATION OF GLOBAL SOLAR RADIATION MONITORED BY ACTINOGRAPHS

Abstract

The objective of this paper is to develop an actinogram scanning and processing computer system based on Digital Image Processing techniques for daily and hourly global solar radiation. Since the collection and processing of information contained in actinogramas are made by hand, subjective interpretations due to lack of training or routine samplings by different observers can induce a distinct systematic errors. The use of techniques based on the concept of Digital Image Processing in the analysis of actinogramas ensure uniformity of the measurement, minimizing read errors, optimizing time and avoiding losses. The proposed software is being developed at the Faculdade de Tecnologia de Botucatu and the actinograms were provided by the Botucatu Weather Station located in Faculdade de Ciências Agronômicas-UNESP-Botucatu. Preliminary analyzes indicate satisfactory performance of the proposed software, generating measures in the same order of magnitude of the reference method for daily values. The proposed software belongs to a project that is still in progress, where routines and various filter techniques are still being implemented and tested in the recognition of the curve of interest to improve the quality of the graphic information processing. The actinograms of the Botucatu Weather Station are being scanned so that the end of the project, the software can be tested with a more consistent and significant database. So, it will be possible to identify data behaviors and temporal trends resulting from application of Digital Imaging Processing techniques in the monitoring of solar radiation by actinographs.