N. Anantharaman

Particle Swarm Optimization Technique Based Design of Pi Controller for a Real-Time Non-Linear Process

Abstract The increasing complexity of modern control systems has emphasized the idea of applying new approaches in order to solve design problems for different control engineering applications. Proportional-Integral-Derivative (PID) control schemes have been widely used in most of process control systems represented by chemical processes for a long time. However, a very important problem is how to determine or tune the PID parameters, because these parameters have a great influence on the stability and the performance of the control system. Computational intelligence (CI), which has caught the eyes of researchers due to its simplicity, low computational cost, and good performance, makes it a possible choice for tuning of PID controllers, to increase their performance. This paper discusses, in detail, the Particle Swarm Optimization (PSO) algorithm, a CI technique, and its implementation in PID tuning for a controller of a real time process. Compared to other conventional PID tuning methods, the result shows that better performance can be achieved with the proposed method. The ability of the designed controller, in terms of tracking set point, is also compared and simulation results are shown.

Design of Controller using Simulated Annealing for a Real Time Process

The Proportional Integral Derivative Controllers have dominated the industries for nearly a century owing to their simplicity, flexibility and efficiency. The demand for developing new algorithms for designing these controllers to cope up with the complexities of the constantly evolving industries have turned the attention of the designers towards evolutionary algorithms like Simulated Annealing(SA). This paper compares the tuning of the PID controllers using SA and traditional methods. The results obtained reflect that using SA tuned controllers improve the performance of the process in terms of time domain and frequency domain specifications. Further the disturbance rejection as well as set-point tracking is being improved with a considerable enhancement in stability of the process.

Removal of Chromium(VI) Ions from Aqueous Solutions and Industrial Effluents Using Magnetic Fe3O4 Nano-particles

The adsorption characteristics of magnetic Fe3O4 nano-particles synthesized by chemical co-precipitation for the removal of chromium(VI) ions from aqueous solutions and tannery effluents have been studied. The composition, size, morphology and magnetic properties of the nano-particles were characterized by FT-IR, XRD, TEM and VSM methods, respectively. Experiments were conducted in batch mode to observe the influence of different parameters such as pH, feed concentration, adsorbent dosage and temperature on the performance of the adsorbent. It was found that when the pH of the system was decreased from 7 to 2, the extent to which Cr(VI) ions were removed increased from 54% to 77%. The adsorption process was found to follow second-order kinetics and the rate constant was evaluated at 30 °C. The Langmuir isotherm was found to provide a good fit to the experimental data. The adsorption capacity of magnetite nano-particles towards Cr(VI) ions at room temperature was 2.9508 mg/g, with the value increasing to 3.4454, 3.7592 and 4.0475 mg/g at 40 °C, 50 °C and 60 °C, respectively. On the basis of the adsorption free energy change of 16.577 kJ/mol obtained at 30 °C, the adsorption mechanism was confirmed as being chemical in nature. The thermodynamic parameters for the adsorption process were also calculated from the experimental data. At an S/L ratio of 0.2 and under optimized conditions of pH, temperature and agitation, the removal of Cr(VI) ions from aqueous solution amounted to 85%. Regression analysis was performed and a correlation between percentage removal and operating parameters obtained.

Simultaneous Informative Gene Extraction and Cancer Classification Using ACO-AntMiner and ACO-Random Forests

Microarray cancer gene expression datasets consist of high dimensional data. Gene selection helps in the removal of irrelevant genes. The reduced dimensions of the datasets help in improving the overall classification performance. We present two hybrid techniques, Ant Colony Optimization-AntMiner (ACO-AM) and ACO-RandomForests (ACO-RF) with weighted gene ranking as heuristics. The heuristic information is obtained by a weighted sum of the Information Gain, Chi-Square, Correlation based Feature Selection (CFS) and Gini Index scores for each gene. The ACO algorithm selects a small subset of relevant genes from this ranking. The fitness’s of these subsets are then assessed by the cAnt-Miner and the Random Forest classifiers. The performances of the algorithms are tested using two cancer gene expression datasets retrieved from the Kent Ridge Bio-medical Dataset Repository. We demonstrate that genes selected by the suggested algorithms yield better classification accuracies.

Influence of Experimental Parameters in the Treatment of Distillery Effluent by Electrochemical Oxidation

The electrochemical oxidation of distillery effluent was studied in a batch reactor in the presence of supporting electrolyte NaCl using Mixed Metal Oxide (MMO) electrode. The effect of operating parameters such as current density, initial pH, and initial electrolyte concentration on the percentage of Chemical Oxygen Demand (COD) removal, power consumption, and current efficiency were studied. The maximum percentage removal of COD was observed to be 84% at a current density of 3 A/dm2at an electrolyte concentration of 10 g/l with an effluent COD concentration of 1000 ppm and at an initial pH of 6. The operating parameters for the treatment of distillery effluent by electrochemical process were optimized using response surface methodology by CCD. The quadratic regression models with estimated coefficients were developed for the percentage removal of COD and power consumption. It was observed that the model predictions matched with experimental values with an R2 value of 0.9504 and 0.9083 for COD removal and power consumption respectively. The extent of color removal and oxidation of organic compounds were analyzed using UV spectrophotometer and HPLC.

Studies on biodiesel production from Pongamia oil using heterogeneous catalyst and its effect on diesel engine performance and emission characteristics

ABSTRACT Commercial calcium oxide (CaO) impregnated with 25 wt% potassium iodide (KI) was prepared by wet impregnation method and adopted for transesterification of Pongamia oil using methanol. The synthesized catalyst (KI/CaO) was characterized using different techniques such as X-ray Diffraction, Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmett-Teller and Scanning Electron Microscopy analysis. Under the reaction conditions of 12:1 methanol:oil ratio, 4 wt% KI/CaO catalyst, 2 h reaction time and at a reaction temperature of 65°C, a maximum biodiesel conversion of 95.7% was obtained. Synthesized biodiesel was characterized by FTIR and H Nuclear Magnetic Resonance Spectroscopy techniques. The performance and emission characteristics of different blends of Pongamia biodiesel and conventional diesel were tested using a single-cylinder, four-stroke IC engine and the results were compared.

Hybrid biogeography based simultaneous feature selection and MHC class I peptide binding prediction using support vector machines and random forests

Accurate detection of peptides binding to specific Major Histocompatibility Complex Class I (MHC-I) molecules is extremely important for understanding the underlying process of the immune system, as well as for effective vaccine design and developing immunotherapies. Development of learning algorithms and their application for binding predictions have thus speeded up the state-of-the-art in immunological research, in a cost-effective manner. In this work, we propose the application of a hybrid filter-wrapper algorithm employing concepts from the recently developed biogeography based optimization algorithm, in conjunction with SVM and Random Forests for identification of MHC-I binding peptides. In the process, we demonstrate the effectiveness of this evolutionary technique, coupled with weighted heuristics, for the construction of improved prediction models. The experiments have been carried out for the CoEPrA competition datasets (accessible online at: http://www.coepra.org) and the results show a marked improvement over the winner results in some situations and comparably good with regard to others .We thus hope to initiate further research on the application of this new bio-inspired methodology for immunological research.

EMULSION LIQUID MEMBRANE PERTRACTION OF METAL IONS FROM AQUEOUS SOLUTIONS AND ELECTROPLATING EFFLUENT USING ROTATING DISK CONTACTOR

Removal of chromium (III), copper (II), and zinc (II) from synthetic aqueous solutions and electroplating wastewater by an emulsion liquid membrane technique (ELM) was studied using a rotating disk contactor (RDC). Kerosene as diluent, Span 80 as surfactant, di-(2ethyl hexyl) phosphate (D2EHPA) as carrier, and 1 N H2SO4 solution as internal stripping phase were used for emulsion preparation. RDC provides relatively low shear to emulsion and thus minimizes rupture of the ELM. Various hydrodynamic and chemical parameters such as metal ion concentration in the continuous (feed) phase, pH of the continuous phase, carrier concentration, agitation speed, internal stripping agent concentration, and flow rate ratio of continuous phase to dispersed phase (treat ratio) have been experimentally investigated. The results showed that it is possible to remove more than 95% of all metal ions from aqueous solutions with a concentration factor of more than 35 and a removal of 68–74% of three metal ions from the electroplating effluent.

CONTINUOUS FOAM SEPARATION OF HEAVY METAL IONS FROM ELECTROPLATING INDUSTRIAL EFFLUENT

Process industries generate a large amount of waste materials during either production or downstreaming operations. Among many methods available for their separation, foam separation plays a major role, especially when the concentration of undesirable components involved is very low. The success of this technique depends on the stability and characteristics of the foam. This operation is simple with less maintenance as there are no moving parts. In the present study, simultaneous removal of metal ions such as chromium (VI), copper (II), and zinc (II) from electroplating industrial effluent was carried out with sodium lauryl sulfate (SLS) as surfactant in continuous foam column. Enrichment ratios of 3.94, 4.05, and 7.96 with a percentage removal of 59.0%, 63.0%, and 99.2% were obtained for chromium (VI), copper (II), and zinc (II) ions respectively at the optimum operating parameters of 23 cm liquid pool height in column, 0.1 liter per minute (Lpm) of airflow rate, feed flow rate of 4 liters per hour (Lph), 0.1% (w/v) of SLS concentration, pH of 6.0, and at feed concentrations of 32.5, 27.0, and 23.0 ppm for chromium (VI), copper (II), and zinc (II) ions respectively. Enrichment ratio was found to increase with an increase in feed flow rate. With a decrease in concentration of the bulk solution, the separation factor was found to increase. The study indicates the feasibility of continuous foam separation for treating industrial effluents.

Modification of polyethersulfone using sericin and polyvinylpyrrolidone for cadmium ion removal by polyelectrolyte-enhanced ultrafiltration

AbstractThe present study deals with the synthesis of polyethersulfone (PES)-based membrane using a biopolymer sericin and polyvinylpyrrolidone (PVP) by phase inversion process. The synthesized membranes were characterized for hydrophilicity, pure water permeability (PWP), membrane stability, and surface functional group analysis. The synthesized membranes were used to study the effective removal of cadmium ions using poly(diallyldimethylammoniumchloride) and polyethyleneimine (PEI) by polyelectrolyte-enhanced ultrafiltration. PVP-sericin-incorporated PES membrane resulted in the highest average pore radius (22 nm) and PWP (34.11 L m−2 h−1 bar−1). It also showed that higher antifouling resistance of 10 folds than neat PES membrane retained the higher flux rate. Overall, PES/sericin/PVP membrane has better characteristics, and maximum percentage of cadmium removal was obtained when added with PEI ligand.