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In recent years, fault diagnosis in the Induction Motor Drive (IMD) has been a popular and important field in the motor-drive research area. The development of control circuits for induction motors has prompted the attention of both researchers and industrialists. This paper proposes a broken bar fault diagnosis using Hilbert Transform (HT) and Artificial Neural Networks (ANN), with the drive regulated through the Indirect Field Orientation Control (IFOC). The HT obtains the spectrum of stator current, which is utilized to identify the Broken Rotor Bar (BRB) failure. The magnitude and side-band frequency of the drive are extracted using the Fast Fourier Transform (FFT), and these parameters are fed into the ANN inputs. The fault severity is computed by the ratio of mean side-band frequency amplitude to the main frequency amplitude for finding the impact of failure in the drive. ANN is used to diagnose failure with high accuracy. The tested and training results are used to attain the minimum Mean Square Errors (MSEs). The IFOC is involved in this proposed system to ensure high performance under the variable speed drives. The proposed scheme is validated in both MATLAB/Simulink and experimental platforms. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effectiveness of the marine macro-algae Ulva pertusa as a potential source of important chemicals, including 2,3-butanediol (2,3-BDO). This study examined how pretreatment conditions like liquid-to-solid ratio, reaction temperature, and reaction time influence the hydrolysis of U. pertusa biomass through hydrothermal pretreatment followed by enzymatic hydrolysis. Consequently, 23.44 g/L (12.7 % based on biomass weight) of reducing sugar was produced under hydrothermal pretreatment conditions (liquid-to-solid ratio of 6:1, reaction temperature of 165 °C, and reaction time of 15 min), followed by enzymatic hydrolysis. During hydrothermal pretreatment, the sugar concentration peaked at 3.68 g/L within the severity factor (SF) range of 3.5–4.4. During subsequent enzymatic hydrolysis, the sugar concentration remained stable until the SF reached 4.0. However, when SF exceeded 4.0, the sugar concentration rapidly decreased. The effectiveness of U. pertusa hydrolysate was evaluated via the fermentation of 2,3-BDO. Pantoea agglomerans successfully produced 2,3-BDO with a yield of 0.299 g/g-sugar from U. pertusa hydrolysate. In summary, this study demonstrated the effectiveness of U. pertusa hydrolysate as a bioresource for producing biochemicals, including 2,3-BDO. • Effectiveness of macro-algae Ulva pertusa as a possible source for 2,3-BDO production. • 23.44 g/L sugar yielded under hydrothermal pretreatment with subsequent enzymatic hydrolysis. • Hydrothermal pretreatment was optimized at 165 °C and 15 min with 6:1 L/S ratio. • Pantoea agglomerans yielded 0.299 g 2,3-BDO/g sugar from hydrolysate of U. pertusa. [ABSTRACT FROM AUTHOR]

On-site production of cellulases using lignocellulosic materials can improve the economic viability of biorefineries. This, however, requires the pretreatment of substrates using thermochemical conditions that can vary in severity. To understand the effect of pretreatment severity on cellulase production by Aspergillus ustus S3 on sugarcane bagasse, we applied NaOH pretreatment corresponding to 3 severity factors (SF1.32, SF1.79, and SF3.64) to generate SCB that was used as inducing substrate. The highest cellulase activity (0.681 U/mL) was obtained with the intermediate severity (SF1.79) while significantly lower activities of 0.495 and 0.539 U/mL were recorded with low (SF1.32) and high (SF3.64) severities, respectively. Chemical and structural characterization revealed that low and intermediate severities improved cellulose accessibility and cellulase titres while high severity impaired them, thus limiting substrate suitability for enzyme production. These results show that though high SFs might be desirable in other applications, moderate severities may be more appropriate for cellulase production. [ABSTRACT FROM AUTHOR]

The aim of this study was to optimize the conditions for subcritical water treatment of krill, as expressed with a single parameter: the severity factor (log R0). Raw krill was treated under subcritical water conditions at various log R0values (1.54–3.75) by varying the treatment temperatures (120–180 °C) and times (0–10 min) in two different sizes of batch-type vessel (10 and 117 mL). The log R0value could efficiently describe changes in various properties of the obtained liquid extracts and solid residues. The most desirable shrimp-like flavor intensity and highest sensory preference were obtained for log R0values of 2.75–3.01. The results also proved that severity factor can be used as a single parameter to control subcritical water treatment conditions in differently sized batch-type vessels to produce shrimp-like flavor extract and residue from krill. Optimization of krill treatment under subcritical water conditions. [ABSTRACT FROM PUBLISHER]