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Patel S.,Ahmedabad University | Thakker R.A.,Vishwakarma Government Engineering College
Journal of Engineering Science and Technology Review | Year: 2016

In this work, we have proposed modified PSO algorithm based optimizer for automatic circuit design. The performance of the modified PSO algorithm is compared with two other evolutionary algorithms namely ABC algorithm and standard PSO algorithm by designing two stage CMOS operational amplifier and bulk driven OTA in 130nm technology. The results show the robustness of the proposed algorithm. With modified PSO algorithm, the average design error for two stage op-amp is only 0.054% in contrast to 3.04% for standard PSO algorithm and 5.45% for ABC algorithm. For bulk driven OTA, average design error is 1.32% with MPSO compared to 4.70% with ABC algorithm and 5.63% with standard PSO algorithm.


Chinchore J.B.,Vishwakarma Government Engineering College
2014 International Conference on Control, Instrumentation, Communication and Computational Technologies, ICCICCT 2014 | Year: 2014

Vehicles are generally identified by their license plates. Locating the exact area containing the license plate is an important step in any license plate recognition system. This work describes an Edge Density Based approach for locating the single/multiple license plates present in the captured frame. The proposed approach is divided into two stages: Pre-processing and Exact detection. Pre-processing involves RGB to Grayscale conversion and Contrast Enhancement. Contrast Enhancement is employed to enable the algorithm to detect license plates at night and in low light conditions. In the second stage after edge detection, Edge Density Based Region Growing is applied to highlight the regions with dense vertical edges that may contain the license plate. The highlighted regions are extracted one-by-one through connected component analysis. These are then subjected to six-different filtering tests to check whether they are license plates or not. The candidates which qualify all the tests are returned as Exact Detected License Plates. To show the effectiveness of the proposed approach a detailed evaluation is done on a database comprising of 810 images captured from India and abroad. This database contains vehicles having license plates of variable size, shape and color captured in different environmental conditions. The proposed approach detects license plates with 91% of accuracy. © 2014 IEEE.


Patel N.,Vishwakarma Government Engineering College | Padhiyar N.,Indian Institute of Technology Gandhinagar
IFAC-PapersOnLine | Year: 2016

Evolutionary Algorithms have been successfully applied for offline optimal control problems of fed-batch bio-reactors. In such problems, productivity-yield maximization is carried out by optimizing the transient feed recipe. However, this is usually done for a fixed fed-batch time. The optimum batch time can be computed by solving single objective optimal control problems multiple times with different fed-batch times. Since this approach is quite computationally expensive, we in this work formulate a multi-objective optimization (MOO) problem to find the minimum fed-batch time along with maximizing productivity-yield. Such an MOO approach will result in saving significant computational effort. A single parameter based fast mesh sorting with multi objective differential evolution is used in this work for solving MOO problems. We have considered a case study of optimal control of fed-batch reactor for secreted protein production with volume constraint in this work. © 2016


Patel N.,Vishwakarma Government Engineering College | Padhiyar N.,Indian Institute of Technology Gandhinagar
IFAC Proceedings Volumes (IFAC-PapersOnline) | Year: 2015

A single parameter based fast mesh-sorting is proposed in this work. The single parameter algorithm as compared to non-dominated sorting eliminates the classification of the population into non-dominated fronts and calculating crowding distance. The proposed one parameter approach also provides flexibility of choosing any probability based selection operator. On the other hand, non-dominated sorting approach can only use tournament selection directly. We have considered Zitzler-Deb-Thieles (ZDT) test functions to test computational and convergence capabilities of proposed algorithm. The performance of the proposed algorithm is compared with conventional Non-dominated Sorting Genetic Algorithm-II (NSGA-II) and NSGA-II with a recent fast corner-sort algorithm. We have also considered optimal control of fed-batch reactor as Multi-objective optimization application. © 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.


Patel N.,Vishwakarma Government Engineering College | Padhiyar N.,Indian Institute of Technology Gandhinagar
IFAC Proceedings Volumes (IFAC-PapersOnline) | Year: 2015

To enhance convergence property of Genetic Algorithm (GA), we in this work propose modification in GA by combining the global search property of GA with a convergence property of Box-Complex method. Using the current population of GA, new members are created using Box-Complex concept, which replaces equal number of worst population members. A comparative study of the proposed GA with the conventional GA and widely accepted Jumping Gene GA (JG GA) is presented in this work. We have considered two mathematical and a batch reactor optimal control applications for evaluating the efficacy of the proposed GA. There are two user defined parameters in the proposed algorithm, namely extent of Box-Complex Assistance(BCA), and expansion/contraction factor. Effect of both these parameters on convergence is presented in this work for the proposed GA. © 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.


Patel N.,Vishwakarma Government Engineering College | Padhiyar N.,Indian Institute of Technology Gandhinagar
Journal of Process Control | Year: 2015

Genetic algorithm (GA) is a popular stochastic optimization technique for past couple of decades and has been successfully applied to numerous applications of single and multi-objective optimization problems. Various modifications in GA are proposed in open literature to increase convergence rate and probability of obtaining global minimum by increasing population diversity. Box Complex is a gradient free optimization method having good convergence property. To enhance convergence property of GA, we in this work propose an extension of GA by combining the global search property of GA with a convergence property of Box Complex method. We add one or more population members created by Box Complex method using the current population and replace the equal number of worst population members every generation. A comparison study of the proposed GA with conventional GA and widely accepted jumping gene GA (JG GA) is presented in this work. We have considered two benchmark optimization functions, namely Rosenbrock's and Ackley's Path function. We also carry out the comparison of GAs for three optimal control problems. One of them is the maximization of product concentration with multiple reactions in a batch reactor. Minimization of the off-spec product during product grade transition in a polymerization reactor is considered as the second optimal control problem. The third test application is optimal control of a non-isothermal plug flow reactor. There are two user defined parameters in the proposed algorithm, namely number of Box Complex Members (BCM), and expansion/contraction factor α. Effect of both these parameters on the convergence profile have been presented in this work for the proposed GA. A statistical summary of ten simulation runs for the proposed GA, JG GA, and conventional GA has been discussed for each of the five applications. © 2015 Elsevier Ltd. All rights reserved.


Sheth C.,Tata Consultancy Services Ltd. | Thakker R.A.,Vishwakarma Government Engineering College
Smart Innovation, Systems and Technologies | Year: 2016

A single firewall becomes traffic bottleneck depending on network expansion, number of connections and throughput required. The present paper describes a method of interconnecting the firewalls at multiple geographic locations through Open source network. The placement of firewall and routing device along with protocols will form the proposed optimized system to improve overall network security and scalability. To evaluate the performance of the approach, authors carried out performance testing under laboratory setup. OpenBSD PF firewalls processed 360 kpps of traffic with 80 % CPU load. Further, design for site requiring higher capacity is proposed and forwarding performance of firewalls is tested with different packet sizes under laboratory traffic by changing maximum transmission unit (MTU). Dynamic extension of design is proposed to connect to other networks using dynamically routed interconnections. © Springer International Publishing Switzerland 2016.


Patel J.,Nirma University | Patel H.,Nirma University | Bhatt C.,Vishwakarma Government Engineering College
Soil and Water Research | Year: 2014

Accurate estimation of evapotranspiration (ETo) is a key factor in weather-based irrigation scheduling methods. To estimate ETo using the Hargreaves equation, just the data on the minimum and maximum temperature and solar radiation are required. However, this procedure cannot offer consistent accuracy for different climate conditions. To attain the accuracy, calibration of the equation constants (CH and EH) for different climate conditions have successfully been attempted by many researchers. Because these calibration procedures are lengthy and location-specific, there is a need of a generalized calibration method to make the Hargreaves equation more pertinent and effective. In this paper, fuzzy logic based calibration method for the Hargreaves equation is proposed and validated. The fuzzy inference system is developed to compute appropriate values of the constants CH and EH on the basis of past data on humidity and wind velocity of a selected location. The underlying relationship between weather conditions and the best values of the constants CH and EH are used to establish a fuzzy rule base. The performance of the method is checked at eight geographically different locations of India with diverse climate conditions. The Mean Absolute Error (MAE) in ETo values estimated by the calibrated modified Hargreaves equation and the Penman-Monteith (PM) equation is in the range of 0.3220-1.0325. It is far more lower than if the error is calculated using the original Hargreaves equation. It confirms the correctness of the calibration method for different climate conditions.


Jain R.K.,Vishwakarma Government Engineering College | Kothyari U.C.,Indian Institute of Technology Roorkee
Journal of Hydraulic Research | Year: 2010

Experimental results are presented on suspended load transport rates of clay eroded from a channel bed made up of two types of cohesive sediment mixtures. The first mixture was prepared using fine gravel and clay with the clay proportion by weight varying from 10 to 50%. In the second mixture, equal proportions of fine gravel and fine sand were mixed with clay in proportions of 10 to 50%. Based on dimensional considerations a computational procedure was developed to estimate the rate of suspended load transport of the clay fraction eroded from the cohesive sediment mixtures. In the absence of cohesion, the proposed computational method transforms to a method for computation of suspended load transport rate of the cohesionless sediment mixtures. Studies on suspended load transport rates of cohesive sediment mixtures containing gravel as presented here were not reported so far in the literature to the best of our knowledge. © 2010 International Association for Hydro-Environment Engineering and Research.


Chinchore J.B.,Vishwakarma Government Engineering College | Thakker R.A.,Vishwakarma Government Engineering College
IEEE International Conference on Circuit, Power and Computing Technologies, ICCPCT 2015 | Year: 2015

In this paper, a low voltage low dropout (LDO) regulator is designed and simulated in 0.13 μm CMOS technology, which converts an input voltage of 1.2V into a stable regulated output voltage of 1.1 V using Ng-Spice circuit simulator. The two stage operational amplifier (Op-Amp) is used as an error amplifier (EA). Here, the Artificial Bee Colony (ABC) evolutionary algorithm based optimizer is demonstrated for solving the problem of the device sizing and other parameters of Op-Amp and optimization. This approach for designing two stage Op-Amp circuit does not require any analytical calculations and handles non-linear effects of sub-micron devices very effectively. The designed LDO is tested for a change in load current for 0-100 mA and it is found that the power supply rejection ratio (PSRR) is found to be 78.5 dB at 1 KHz and 28.7 dB at 10 MHz. The settling time of less than 1 μsec observed during testing of line and load regulations. © 2015 IEEE.

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