CEFOP student improves the process of estimation baseline in mixed spectra

Roberto Carvajal, associated student to Center for Optics and Photonics, at Universidad de Concepción, got his Master of Science in Engineering degree with specialization in Electrical Engineering, for an investigation that began three years ago and told under the Dr. Luis Arias guide.

IMG_1936-500x375“Removal baseline, based on the technique of the sampled base” is the name of the work presented by Carvajal, whose exposure was evaluated with the highest rating by the Commission. The thesis is about the estimation of continuous spectral characteristics of a particular process, which has continuous and discontinuous spectral radiation, through a principal component analysis. Thus, it is possible to recover the discontinuous characteristic by subtracting the continuous spectrum estimated through the use of new techniques, oriented sensing spectral information of processes or phenomena, by statistical analysis, new algorithms for spectral estimation and local optical sensors (radiometers).

As Roberto Carvajal explained, the work topic was chosen to follow a line of research established in undergraduate. “At that time, I did something tangible: a system for sensing, and here we referred to estimation and optimization algorithms, more theoretical than practical. The idea came under the eaves of 11110364 FONDECYT project, led by Professor Luis Arias, for quite some time, and when I was in undergraduate, I took it and could develop it to this Masters program that ended today”, he said.

In total, the investigation lasted a little over three years. “When I entered the Magister program, I was an undergraduate student. Once I left undergraduate, the next week I was offered to work in Santiago, a good opportunity and I agreed, but I kept also devoted to Magister, although it was difficult, because it meant traveling, because in Santiago I had no contact with professor, rather than by email, and sometimes things need to be talk and think  together a bit”, he said about the difficulties he faced to get the Magister degree.

For his part, Dr. Luis Arias Carvajal highlighted Roberto’s commitment to end his Master process, and also stressed the advances involving the results of research work, developed at our center in the future. “Roberto is very proactive and that should be an important feature in our Center students. That earned him a big advantage that allowed him to take forward this work. Roberto’s work was based on an article published in a conference 2012 in Madrid, related to an experiment in which we adapted the techniques of spectral recovery, for use as an algorithm for estimating baseline. When a spectrum is measured from a process, it generally contains low frequency spectral regions of the spectrum and add line spectra, or call it high frequency. Today, there are groups working to separate the two types of information when they are independent. In 2012, we designed a novel technique, which functions demonstrated basis for estimating continuous spectra. What made Roberto was to optimize the sampling process. Tested the article was sent to publication and are awaiting the decision of the reviewers”, said professor Carvajal.

As for future plans, Carvajal, highlights his current job stability. “With this, for me the course of study was fulfilled. It was something that was pending and several times I thought of ‘throwing in the towel’, but sonmething that encouraged me to continue was my family and professor Carvajal, to not to abandon the studies. I am now OK at my workplace and doing class in Duoc”, said the young researcher.

Regarding the practical application of the results, Dr. Arias said: “There are processes that can be monitored using radiometers. In particular, we worked on combustion processes, where we observed with radiometers, the radiation spectrum of hydrocarbon flames and, based on this spectrum, we can estimate if the burning is either efficient or inefficient. These spectra contain continuous and discontinuous parts, and both processes are independent, therefore, we apply this technique to separate the information. Thus we can determine if the performance of the combustion process is efficient or inefficient. With this technique, processing times are much faster and more direct on the discontinuous spectra, compared with the algorithms that have been developed so far”, said CEFOP researcher .



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