Raghu Institute of Technology

Vishākhapatnam, India

Raghu Institute of Technology

Vishākhapatnam, India
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Tangeti V.S.,Raghu Engineering College | Vasundhara D.,Raghu Institute of Technology | Naresh Kumar M.,Raghu Institute of Technology | Mylapalli H.,Raghu Engineering College | Kumar K.S.P.,GVK Biosciences Pvt. Ltd.
Asian Journal of Chemistry | Year: 2017

A series of novel C3-dihydrofuran substituted 1H-benzo[g]chromene-2,5,10-triones were synthesized and characterized by spectral analysis. The target molecules were screened for their antimicrobial and anticancer activities and structure and activity relationship (SAR) was investigated. Structure and activity relationship studies revealed that the compounds 6p, 6q, 6s, 6t were found to be more active in antimicrobial screening. Antiproliferative properties were evaluated against human cancer cell lines, namely, laryngeal carcinoma (Hep2), lung adenocarcinoma (A549) and cervical cancer (HeLa). The best among them, C3-dihydrofuran substituted 1H-benzo[g]chromene-2,5,10-trione with methoxy group substitution at ring A and B were selected for further structure activity relationship. Among the derivatives, (2S,3S)-propyl-4-acetyl-5-(7,9-dimethoxy-2,5,10-trioxo-5,10-dihydro-2H-benzo[g]chromen-3-yl)-3-(3,5-dimethoxyphenyl)-2,3-dihydrofuran-2-carboxylate (6t) showed most potent cytotoxic activity against all the three cancer cell lines. Toxicity studies revealed that dihydrofuran substituted 1H-benzo[g] chromene-2,5,10-triones (6a-t) are specifically target the cancer cell lines. © 2017, Chemical Publishing Co. All rights reserved.

Subbarao M.,VFSTR University | Satyanarayana S.,Raghu Institute of Technology
Cogent Engineering | Year: 2017

Design and implementation of a current controlled single stage single phase integrated AC/DC isolated Power Factor Correction (PFC) converter is presented in this paper. With the integrated topology reduces the number control switches. The proposed converter has the advantage of low bulk capacitor voltage and only single control switch hence reduce in complexity in control and cost. Sub-harmonic oscillations which are produced in conventional current controller. By adding an external compensating signal effect of oscillations are reduced and performance of the converter is improved. The proposed scheme is implemented in real time by TMS320F2812 digital signal processor (DSP) board. The performance of converter is verified both experimentally and by simulation at different load and line conditions. The proposed converter is designed for 90–230 V, 50 Hz AC input, 48 V DC output and operating at 100 kHz switching frequency. The Experimental results shows that the DSP-based fuzzy controlled single phase single switch integrated PFC converter achieve high power factor and satisfies IEC-61000-3-2 and other European input current harmonic limits for Class-C & Class-D applications. © 2017 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license.

Maheswara Rao C.,Raghu Institute of Technology | Venkatasubbaiah K.,Andhra University
International Journal of Grid and Distributed Computing | Year: 2016

In the present work, an investigation has been made to study the effect of cutting parameters (speed, feed and depth of cut) on the multi-responses, Material Removal Rate (MRR) and Surface Roughness (R a). The experiments were done on a conventional lathe using a tungsten carbide tool under dry environment. Twenty seven alternative combinations of speed, feed and depth of cut were considered (as per Taguchi’s standard L27 Orthogonal Array) for the machining of medium carbon steel EN8. For the optimization of multi-responses, the Multi-criteria decision making (MCDM) method, TOPSIS has been employed. Main effect plot for the Signal-to-Noise (S/N) ratios of the relative closeness coefficient (C i +) was drawn using the MINITAB-16 software. From the TOPSIS and the main effect plot drawn for the relative closeness coefficient (C i +), the optimal combination of the multi-responses were found at 27th alternative i.e. speed at 760 rpm, feed at 0.3 mm/rev and depth of cut at 1.5 mm respectively. The analysis of variance (ANOVA) has been done to know the influence of cutting parameters on the multi-responses. From the ANOVA results of the relative closeness coefficient (C i +), it is found that the feed has high influence (F =41.08) followed by the depth of cut (F =25.78) and speed (F = 22.55). © 2016 SERSC.

Satish Rama Chowdary P.,Raghu Institute of Technology | Mallikarjuna Prasad A.,UCoE | Mallikarjuna Rao P.,Andhra University
Advances in Intelligent Systems and Computing | Year: 2014

Multi resonant structure is one of the solutions for broadband characteristics in patch antennas. Thick substrate materials with low dielectric constant are also favourable for such characteristics. In this paper, the combination of E and U shaped slots on the patch antenna along with above mentioned substrate material properties is designed, fabricated and analysed. The characteristics of the designed antenna are studied with respect to the reports like reflection coefficient, VSWR plot, and radiation pattern. The proposed antenna exhibited a wide bandwidth of 4GHz. The effect of the material properties and the physical parameters on the broadbanding are also observed. © Springer International Publishing Switzerland 2015.

Chakravarthy V.V.S.S.S.,Raghu Institute of Technology | Rao P.M.,Andhra University
2nd International Conference on Electronics and Communication Systems, ICECS 2015 | Year: 2015

Locating nulls in the desired directions and as well as steering main beam towards the direction of interest is the most important part of the beamforming concept. Many evolutionary and metaheuristic algorithms are applied to solve these problems. In this paper a circular array is considered. Novel flower pollination algorithm is applied to position nulls with and without beam steering conditions and compared with those obtained using genetic algorithm. © 2015 IEEE.

Chakravarthy V.V.S.S.S.,Raghu Institute of Technology | Rao P.M.,Andhra University
Proceedings of 2015 IEEE International Conference on Electrical, Computer and Communication Technologies, ICECCT 2015 | Year: 2015

Null positioning and beam steering are the basic building blocks of Beamforming. Nulls in the radiation pattern of a radiating element are characterized by minimum radiation in the direction of its position. They suppress any radiation received in its direction. Some traditional numerical and computational intelligent heuristic techniques are proposed to position and steer nulls. In this paper simple Genetic Algorithm is used to position the nulls in the desired locations in the radiation pattern of a circular array. Nulls with predefined null depths are obtained with and without side lobe level (SLL) constraint. The convergence plots have shown the impact of the SLL constraint on the convergence. © 2015 IEEE.

Prasad V.,Raghu Institute of Technology | Rao T.S.,Gandhi Institute of Technology and Management | Babu M.S.P.,Andhra University
Soft Computing | Year: 2016

This work is a hybrid architecture design furnished successfully using artificial intelligence techniques, rough data sets theory and machine learning algorithms. The purpose of this work is to bring the spotless and smart approach in identifying the thyroid disease in a human. There are several mechanisms implemented on thyroid data sets which produced astonished outcomes, but the data considered for the thyroid disease diagnoses (TDD) is inconsistent, redundant and consists of missing attribute values as per my literature survey. The proposed work is to construct an expert advisory system of hybrid architecture, which is to determine the optimistic disease growth because of the thyroid gland. A string matching system (SMS) was at the outset developed, which can predict the actual TDD based on the knowledge available. If the SMS fails, an individual approaches using artificial bee colony optimization and particle swarm optimization are developed to achieve the accuracy of results appreciating the measure values as 65 and 93 %, but the results obtained using the above said approaches are calculated using some missed attribute values which are not included in the knowledge likewise left blank and hence the proposed work continues to first generate the missing attribute value in the knowledge by using rough data sets theory and the obtained data (missed attribute values) is given to predict optimistic disease along with its prevention and its curing methods. However, the data generated cannot predict the optimal disease and hence it is proposed to use a machine learning algorithm so that, obtained result is hygienic. The knowledge for implementation of this work is gathered from Intelligent System Laboratory of K.N. Toosi University of Technology, Imam Khomeini Hospital. A questionnaire form is developed for providing an interface for user so they can contribute the data. © 2015, Springer-Verlag Berlin Heidelberg.

Srinivas N.S.,Andhra University | Chakravarthy V.V.S.S.S.,Raghu Institute of Technology | Kumar T.S.,Vishnu Institute of Technology
Advances in Intelligent Systems and Computing | Year: 2016

Shield Effectiveness (SE) is a most significant parameter that determines the electromagnetic compatibility (EMC) characteristics of the system. Calculation of this parameter is the prerequisite for understanding the standards of the system. Many techniques are implemented for the betterment of this parameter. In this paper, implementation of various perforated shield materials are proposed and their corresponding frequency responses are evaluated. Distance between the source of electromagnetic interference (EMI) and the system under test (SUT) has a direct impact on SE. Investigations by varying this distance is presented in this paper. The functioning of the material as shield in the presence of such environment is given. © Springer India 2016.

Chowdary P.S.R.,Raghu Institute of Technology | Rao P.M.,Andhra University
2014 International Conference on Electronics and Communication Systems, ICECS 2014 | Year: 2014

The Sierpinski (SPK) geometry has a paramount application in multiband antennas. The multifrequency characteristics of the SPK are characterized by its scaling factor and successive iterations. To allocate more number of bands the geometry has to undergo more number of iterations which makes the antenna more complicated for fabrication. In this work we propose modifications to the SPK geometry with the ability of allocating two frequencies close to WLAN applications. The designed antenna preserved its multiple frequency characteristics and are verified with the radiation plots. © 2014 IEEE.

Devi P.C.,Raghu Institute of Technology | Anusha K.,Raghu Institute of Technology | Kalpana M.,Raghu Institute of Technology | Ganesh L.,ANITS
International Conference on Electrical, Electronics, Signals, Communication and Optimization, EESCO 2015 | Year: 2015

The words broadcasting, unicasting and multicasting are the well familiar terms in the field of communications and are very important in describing various parameters in designing the system. In the field of communications, the applications which involve broadcasting needs an antenna of high directivity and should use the power effectively (low side lobes). Where in applications that needs unicast-reception mainly needs high directivity (Zone of reception) and low interference (low side lobes) antennas. There are some special applications like tracking radars, surveillance antennas demand patterns with special characteristics (Beam widths). Due to the non complexity in implementation and ability to produce symmetrical-high directive beams, generally planar array antennas are used in above mentioned applications. Planar antennas, with compromise in increased number of elements and size, produces high directive beams. Other way of generating desired beam pattern is by synthesizing the antenna radiation pattern. Schelkunoff polynomial synthesis method is one being used in linear array design for suppressing radiation in undesired directions, there by increases the directivity. In order to produce the desired beam with high directivity this paper proposes a planar array design method and also extends the schelkunoff polynomial method (confined as linear array synthesismethod ) to planar array design to produce cost effective high directive antennas. The radiation pattern characteristics (RPC) Directivity, 3dB beam width, Null-Null beam width and side lobe levels are used to analyse the performance of proposed design and algorithm. © 2015 IEEE.

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