Implementation of Pre Compensation Fuzzy For a Cascade PID Controller Using Matlab Simulink

Fuzzy logic control technology has been widely and successfully utilized in numerous industrial applications. Since fuzzy logic with humanlike but systematic properties can convert linguistic control rule based on expert knowledge into automatic control strategies, it can be well applied to control the process with un modeled and nonlinear dynamics. In this paper a fuzzy logic based pre compensation scheme for PID controller is proposed. Fuzzy methods can be used effectively to implement conventional control methods for performance improvement. The scheme is based on graphically studying the source of steady state errors arising from applying PID type schemes of systems with dead zones. This work is based on trying to compensate for overshoot and undershoot by the transient response. This is easy to implement in practice since an existing PID controller can be used in conjunction with the fuzzy pre compensator without modification Keywords: Fuzzy controller, PID Controller ,Fuzzification, Defuzzification

Study on the Influence of Rapid Prototyping Parameters on Product Quality in 3D Printing

This work aims at evaluating the relative significance of the input parameters on the product quality produced by Z510 3DP rapid fabricator. Taguchi’s L18 orthogonal array was employed to investigate the possible process parameters including binder setting saturation value (shell & core), layer thickness, and build orientation. Using a surface profilometer and CMM, a series of measurements in evaluating the 3DP products surface finish and dimensional accuracy has been carried out. Nonlinear regression model was developed and a statistical analysis was done to determine the significant factors affecting the product quality of the fabricated products. Optimal process parameter settings were proposed using Particle Swarm Optimization technique. The results were validated by conducting the confirmatory experiments.Mechanical Engineerin

Dial variations in temperature, salinity and dissolved oxygen from the neritic waters off Cochin during April (peak summer)

Dial variations of important hydrographic parameters were studied continuously for 7 days at a 100 m depth station off Cochin. The frequency of observations varied from 1-3 hourly intervals. In surface waters, the ranges in temperature, salinity and dissolved oxygen values recorded during 10-17 April were 30.64°-32.36°C, 34.56- 34.68 X lO''' and 4.06-4.65 ml/1 respectively. Tlie STD profiles in the diurnal study revealed clearly the premonsoon warming (30°-31°C) in the upper 0-30 m depth zone. In the water column up to 50 m depth, mean salinity values ranged from 34.6 to 35 X 10 while dissolved oxygen values were above 4 mI/1. Time series observations on the production and utilisation of dissolved oxygen revealed wide fluctuation from hour to hour. Vertical gradients in the diurnal study indicated the existence of thermocline around 60 m depth with sharp decline in temperature and dissolved oxygen and increase in salinity below 60 m. The diurnal variation on the distribution of temperature and dissolved oxygen exhibited significant rhythmic tidal impulse of a semi-diurnal wave pattern which was more prominent in the bottom layer below 60 m

Effect of addition of SiC particles on the Microstructure and Hardness of Al-SiC composite

This work aims to investigate the effect of the addition of silicon carbide particles on the microstructure and the hardness of the Al-SiC metal matrix composites. The said composite is prepared using the stir casting technique for different weight percentages of the SiC particles. The higher composition of the reinforcement causes the clustering of the particles in the matrix. Thus, research has to be carried out on the aluminum-silicon carbide composites with the reinforcement 3wt%, 6wt%, 9wt%, and 12wt% of SiC particles to obtain the optimized composition. In order to study the microstructure and the reinforcement distribution in the matrix, a scanning electron microscope is utilized. The hardness testing has been carried out using the Vickers’ indentation technique for the as-cast and age hardening conditions. From the microstructural study, it is observed that the microstructure of the said composite exhibits the uniform distribution of the reinforcement. The EDX results show the presence of the reinforcing elements in the Al-SiC composite. From the results obtained from the hardness testing, it is observed that the presence of the carbide element in the composite increases the hardness of the Al-SiC particulate composites

Planting methods, subsurface drip fertigation and bioinoculants on growth and productivity of vetiver [Vetiveria zizanioides (L.) Nash]

A field experiment was conducted to study the effect of three planting methods, (planting in coconut husk mulched trenches, planting in coconut husk lined trenches and planting on the ridges), two levels of fertigation (subsurface drip fertigation and without fertigation) and two levels of bioinoculants (combined application of bioinoculants and without bioinoculant) on growth and productivity of vetiver. The study revealed that planting vetiver slips in coconut husk lined trenches could considerably increase vegetative growth, root yield, net returns and B: C ratio. Subsurface drip fertigation and combined application of bioinoculants with Azospirillum, Fluorescent pseudomonads and AM fungi showed positive effect on growth characters and root yield. However, subsurface drip fertigation was not effective in increasing net income. &nbsp

Bifurcation of rotating liquid drops: Results from USML-1 experiments in space

Experiments on rotational bifurcation of liquid drops, in which the drops were levitated and spun using acoustic fields in a low-gravity environment, were conducted during the first United States Microgravity Laboratory (USML-1) Space Shuttle flight. The experiments have successfully resolved the discrepancies existing between the previous experimental results and the theoretical predictions. In the case of a spherical drop, for which theory exists, the results agree well with the predictions. In the case of flattened drops, the experiments have extablished a family of curves, with the spherical drop as the limiting case

A COMPARATIVE STUDY ON THE IN-VITRO ANTIMICROBIAL ACTIVITY OF THE ROOTS OF FOUR THOTTEA SPECIES

Objective: The main objective of the present study was to investigate the antimicrobial activity of the methanol extract of the roots of four Thottea species. Methods: The root extracts of four Thottea species were subjected to antimicrobial assay by Minimum Inhibitory Concentration (MIC) and Agar Disc diffusion Assay against various medically important pathogens. Results: It is evident from the study that. Significant antibacterial activity was recorded by Thottea sivarajanii and highest activity was recorded against Pseudomonas aeruginosa and Staphylococcus epidermis (64 µg/ml). Out of the four extracts tested for antifungal activity, Thottea barberi and Thottea ponmudiana recorded significant antifungal activity and the highest activity was recorded by T. barberi against Trichophyton rubrum (16µg/ml). Conclusion: Results offer a scientific basis for the traditional use of Thottea species in the treatment of microbial infections, showing that the plant extract has an enormous potential as a prospective alternative drug against microbial pathogens. The present study lays the basis for future studies, to validate the possible use of Thottea species as a candidate in the treatment of microbial infections

Melamine formaldehyde-metal organic gel interpenetrating polymer network derived intrinsic Fe-N-doped porous graphitic carbon electrocatalysts for oxygen reduction reaction

Fe, N doped porous graphitic carbon electrocatalyst (Fe-MOG-MF-C), obtained by pyrolysis of an Interpenetrating Polymer Network (IPN) comprised of melamine formaldehyde (MF as hard segment) and Metal-Organic Gel (MOG as soft segment), exhibited significant Oxygen Reduction Reaction (ORR) activity in alkaline medium. BET surface area analysis of Fe-MOG-MF-C showed high surface area (821 m2 g-1), while TEM, Raman and XPS results confirmed Fe and N co-doping. Furthermore, a modulated porous morphology with a higher degree of surface area (950 m2 g-1) has been accomplished for the system (Fe-MOG-MFN-C) when aided by a sublimable porogen, such as naphthalene. XPS results further demonstrated that these systems exhibited a better degree of distribution of graphitic N and an onset potential value of 0.91 V vs. RHE in 0.1 M KOH solution following an efficient four-electron ORR pathway. The electrocatalytic activity of Fe-MOG-MFN-C is superior to that of Fe-MOG-MF-C by virtue of its higher graphitic N content and surface area. Thus, the study presents a new class of IPN derived MF-MOG nanocomposites with the potential to generate extended versions of in situ Fe-N doped porous graphitic carbon structures with superior ORR activity

Analysis of BH3-only proteins upregulated in response to oxygen/glucose deprivation in cortical neurons identifies Bmf but not Noxa as potential mediator of neuronal injury

Stress signaling in response to oxygen/glucose deprivation (OGD) and ischemic injury activates a group of pro-apoptotic genes, the Bcl-2 homology domain 3 (BH3)-only proteins, which are capable of activating the mitochondrial apoptosis pathway. Targeted studies previously identified the BH3-only proteins Puma, Bim and Bid to have a role in ischemic/hypoxic neuronal injury. We here investigated the transcriptional activation of pro-apoptotic BH3-only proteins after OGD-induced injury in murine neocortical neurons. We observed a potent and early upregulation of noxa at mRNA and protein level, and a significant increase in Bmf protein levels during OGD in neocortical neurons and in the ipsilateral cortex of mice subjected to transient middle cerebral artery occlusion (tMCAO). Surprisingly, gene deficiency in noxa reduced neither OGD- nor glutamate-induced neuronal injury in cortical neurons and failed to influence infarct size or neurological deficits after tMCAO. In contrast, bmf deficiency induced significant protection against OGD- or glutamate-induced injury in cultured neurons, and bmf-deficient mice showed reduced neurological deficits after tMCAO in vivo. Collectively, our data not only point to a role of Bmf as a BH3-only protein contributing to excitotoxic and ischemic neuronal injury but also demonstrate that the early and potent induction of noxa does not influence ischemic neuronal injury

Anti-cancer activity of novel dibenzo[b,f]azepine tethered isoxazoline derivatives

10.1186/1472-6769-12-5BMC Chemical Biology12