Diagnostics of Advanced Power Intensive Power Sources Based on the Acoustic Spectroscopy Method

Objective of this article is to develop a method for lithium chemical current sources diagnostics, which would ensure high reliability in assessing their technical state (primarily, the discharge degree) close to potentially achievable introduction of the acoustic spectroscopy method. Today, microcalorimetric studies and methods of impedance and noise spectroscopy make it possible to predict the lithium chemical current sources service life. However, implementation of the microcalorimetric studies result requires a lot of time accompanied by using stationary and large-size equipment, which is practically impossible in the autonomous conditions. Application of the impedance spectroscopy method provides satisfactory results only with high degrees of discharge. In the range of 0--30 %, it is very difficult to determine the discharge degree, since noticeable alteration in the correlate within its deviation from the mean value is missing. In this regard, it is proposed in order to provide diagnostics of the lithium chemical current sources in the region of initial degrees of discharge to introduce the noise diagnostics method. In order to increase reliability of the diagnostic estimates, it is advisable to use acoustic spectroscopy as a physically independent method in diagnosing the state of lithium chemical current sources. Results of the preliminary measurements analysis confirm the prospects of using the acoustic spectroscopy method in assessing the current state of primary lithium chemical current sources. Experimental studies of the lithium chemical current sources response to acoustic (mechanical) action made it possible to determine a set of parameters characterizing the proposed methodological approach. This provided a possibility to search for correlation dependences of the lithium chemical current sources spectral characteristics on the degree of their discharge. This makes it possible to use the method of acoustic spectroscopy in prompt and reliable diagnostics of the primary current sources in the region of low discharge degrees

Development of a Novel Acoustic Spectroscopy Method for Detection of Eggshell Cracks

Non-destructive testing (NDT) for eggshell faults is highly important for the egg industry, as cracked eggs account for around 3% of total production. The most commonly used method at present, candling, is labor intensive, while computer vision systems are expensive and complicated. In this paper, we present a simple, yet efficient, novel method for eggshell crack detection by acoustic spectroscopy. Altogether, 693 sound recordings were evaluated by different classification methods. The results show a cross-validated 2.1% total classification error, with only 0.87% false positive rate, which is the crucial metric for fresh eggs. Adapting the developed method to an industrial setting may lead to a reliable, fast and cost-effective detection method.

PREDIKSI CEPAT KUALITAS AIR MENGGUNAKAN LPAS (LASER PHOTO-ACOUSTIC SPECTROSCOPY) DENGAN MENERAPKAN METODE KOREKSI CUTTING EDGE FILTERING

A tool that can predict water quality by capturing sound vibrations generated by collisions between water samples and light is LPAS (Laser Photo-Acoustic Spectroscopy). To process the data acquired by LPAS, spectrum correction is needed to eliminate data errors when making acquisitions on water samples. The correction method used in this research is the cutting edge filtering correction method. The regression model that can be used is the PLSR (Partial Least Square Regression) regression model. This research was conducted in the Instrumentation and Energy Laboratory, Agricultural Engineering Study Program, Faculty of Agriculture, Syiah Kuala University. Water sample analysis was carried out at the Laboratory of the Industrial Research and Standardization Center (BARISTAND) Banda Aceh. This study used 4 monitoring wells within the TPA (Final Disposal Site) and 4 samples were taken from community wells outside the scope of TPA Gampong Jawa, Banda Aceh City. The results of this study indicate the parameters (temperature, turbidity, Ph, TSS, DO, BOD and Nitrate) are predicted to be in the frequency range 4000 - 10,000 cm-1. Raw spectrum data for pH and Nitrate (NO3-) parameters produce better data than the spectrum data for cutting edge filtering correction methods while cutting edge filtering spectrum data for temperature, turbidity, TSS, DO and BOD-5 parameters are better than spectrum raw data. This study also shows that the cutting edge filtering correction method is able to cut boundaries and compress the spectrum so that it can provide data limits on the spectrum so that the PLSR method can be applied to predict water quality. Keywords: water quality; Laser Photo-Acoustic Spectroscopy, correction method, regression method

INFLUENCE OF MAGNETIC NANOPARTICLES ON ACOUSTIC ATTENUATION IN LIQUIDS

Magnetic fluids with nanoparticles dispersed in water or oils offer attractive applications in biomedicine and industry. Biocompatible magnetic fluids are used for diagnostics and therapy in medical applications, in pharmacy, and biosensors. Application of ferrofluids is expanding into energy conservation, faster and efficient cooling, and hence better performance in a wide variety of practical applications (in heat exchangers, mainly in micro-cooling systems). For the study of the influence of an external magnetic field on the aggregation processes of magnetic nanoparticles in magnetic fluids, acoustic spectroscopy was used. The jump changes of the magnetic flux density at various temperatures influenced the acoustic attenuation. The measured changes were results of nanoparticle aggregations into new structures.