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Mallikarjuna Rao, P.
- Conservation of Nelapattu Bird Sanctuary - a Review
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Indian Forester, Vol 138, No 10 (2012), Pagination: 941-951Abstract
Nelapattu Bird Sanctuary (Lat. 13°49' N to 31°51' N; Long. 79°57' E to 59°15' E) is located towards west of East coast of Bay of Bengal and about 20 km west of Pulicat Lake near Sullurpet, Nellore District, Andhra Pradesh. It is one of the biggest pelicanery having approximately 1500 pelicans (Pelecanus philippensis) breeding and roosting. It is also an ideal roosting and breeding for long distant and local migrant birds. Vertical gradient and resource partitioning of migratory birds on Barringtonia tree in Nelapattu Bird Sanctuary is being observed. A gradual and natural domination of open bill storks is observed over a period of time. A review on management of Nelapattu Bird Sanctuary is described for ecological sustainability which include irrigation water management, deweeding and prevention of algal bloom, Prosopis juliflora plantation for roosting of birds, plantation of Subabul trees for procuring nesting material. Feeding of st Krishna river water to last only up to May/June 1st week only to avoid stabilization of new summer birds which might compete for space. A statistical relationship worked out between monsoon rainfall and pelican migration.Keywords
Conservation, Nelapattu Bird Sanctuary Pelicans (Pelecanus philippensis)
- Design and Analysis of Broadband Beamspace Adaptive Arrays Using Fractional Fourier Transform
Abstract Views :273 |
PDF Views:0
Authors
Affiliations
1 Dept. of Electronics and Communication Engineering, College of Engineering, (AITAM), Tekkali, IN
2 Dept. of Electronics and Communication Engineering, AUCE, Visakhapatnam, IN
3 Dept. of Electronics and Communication Engineering College of Engineering, (AITAM), Tekkali, IN
1 Dept. of Electronics and Communication Engineering, College of Engineering, (AITAM), Tekkali, IN
2 Dept. of Electronics and Communication Engineering, AUCE, Visakhapatnam, IN
3 Dept. of Electronics and Communication Engineering College of Engineering, (AITAM), Tekkali, IN
Source
International Journal of Electronics and Communication Engineering, Vol 5, No 2 (2012), Pagination: 193-206Abstract
The beamwidth of a linear array depends on number of elements in the array and frequency of the input signal. At present designing of wideband antennas and beamformers became important in the fields of microphone arrays intended for teleconferencing, in transmitting or receiving spread spectrum signals, crip signals etc. A beamspace adaptive planar array for broadband beamforming is proposed based on the filter-and-sum beamforming technique and the required filters are implemented using fractional Fourier Transform. A detailed design method was provided for adaptive arrays and simulation results are provided for the proposed method. The results obtained shows that fractional Fourier Transform filter method is superior in interference rejection compared to conventional finite impulse response filter method.Keywords
Antenna Arrays, Linear Arrays, Broadband Antennas, Adaptive Antennas, Constant Beam Width, Interference Rejection, Filter–and–Sum Beamformer, Fractional Fourier Transform (FrFT)References
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- Srinivasa rao A. S., Mallikarjuna rao P., Muralidhar P. V. and Nayak S. K. (2010): Frequency Invariant beampatterns Using Fractional Fourier Transform, International J.of Multidispl. Research & Advcs. in Engg. (IJMRAE), 2(II), pp.123-134.
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- Srinivasa rao A. S., Mallikarjuna rao P., Jaya E., and Ashokkumar V. (2011): An alternative approach to design and analysis of broadband beamspace adaptive arrays, International J. of Engineering Science and Technology, 3(9), pp.7029 – 7036.
- Generation of Narrow Beams from Thinned Circular Antenna Array with Dipole Elements using BAT Algorithm
Abstract Views :160 |
PDF Views:3
Authors
Affiliations
1 Department of ECE, GIT, GITAM University, Visakhapatnam – 45, IN
2 Department of ECE, AU College of Engineering, Andhra University, Visakhapatnam-03, IN
3 Department of ECE, AU College of Engineering, Andhra University, Visakhapatnam-03, IN
1 Department of ECE, GIT, GITAM University, Visakhapatnam – 45, IN
2 Department of ECE, AU College of Engineering, Andhra University, Visakhapatnam-03, IN
3 Department of ECE, AU College of Engineering, Andhra University, Visakhapatnam-03, IN
Source
Wireless Communication, Vol 7, No 9 (2015), Pagination: 296-300Abstract
The Circular Antenna Array with Dipole radiators is practical antenna array to scan the entire azimuthal plane. The beams with narrow beamwidth and less side lobe level are very useful point to point communication. As the Circular Antenna Array suffers with high sidelobe level and broad beam problems an attempt is made here to reduce these radiation parameters with an efficient metaheuristic optimization technique BAT algorithm. Thinning process is applied on the optimized array for better results. An extensive comparison is brought out between optimized thinned array and uniformly distributed fully populated array.Keywords
Circular Antenna Array, Dipole, Narrow Beams, Bat Algorithm and Thinning.- Solid-State Fermentation for the Production of L-Asparaginase by Aspergillus Sp
Abstract Views :154 |
PDF Views:0
Authors
Affiliations
1 Dept. of Biotechnology, KLR Pharmacy College, Paloncha-507115, Khammam- District, A.P, IN
2 Oil Technological Research Institute, JNT University, Anantapur–15001, A.P, IN
3 International Medical University, Kualalumpur, -57000, MY
1 Dept. of Biotechnology, KLR Pharmacy College, Paloncha-507115, Khammam- District, A.P, IN
2 Oil Technological Research Institute, JNT University, Anantapur–15001, A.P, IN
3 International Medical University, Kualalumpur, -57000, MY
Source
Research Journal of Pharmacognosy and Phytochemistry, Vol 1, No 1 (2009), Pagination: 21-25Abstract
Production of L-asparaginase employing Aspergillus sp. VEM-9 under solid-state fermentation was optimized. Different substrates like rice bran, green gram bran, wheat rawa, wheat bran, Bombay rawa, black gram bran, barley, saw dust, jowar flour, rice flour, castor oil cake, ground nut oil cake, coconut oil cake, sesame oil cake were studied to optimize the best substrate. Groundnut oil cake showed the highest enzyme yield. Different physical fermentation factors were optimized. The maximum productivity of L-asparaginase (60 U/gds) was achieved by employing groundnut oil cake and optimized process parameters including incubation period of 5 days, initial moisture content of solid substrate 90%, 1: 10 (v/w) ratio of salt solution to weight of groundnut oil cake, inoculum level 20%(v/w), incubation temperature at 30°C and initial pH 6.5.Keywords
L-Asparaginase, Aspergillus sp. VEM-9, Groundnut Oil Cake, Optimization, Solid-State Fermentation.- Optimization of Process Parameters for the Production of L-Asparaginase from an Isolated Fungus
Abstract Views :138 |
PDF Views:0
Authors
Affiliations
1 Dept. of Biotechnology, KLR Pharmacy College, Paloncha-507115,Khammam- District, A.P, IN
2 Oil Technological Research Institute, JNT University, Anantapur–15001, A.P, IN
3 International Medical University, Kualalumpur, 57000, MY
1 Dept. of Biotechnology, KLR Pharmacy College, Paloncha-507115,Khammam- District, A.P, IN
2 Oil Technological Research Institute, JNT University, Anantapur–15001, A.P, IN
3 International Medical University, Kualalumpur, 57000, MY
Source
Research Journal of Pharmacognosy and Phytochemistry, Vol 1, No 1 (2009), Pagination: 30-34Abstract
The extracellular L-asparaginase production by fungi isolated from soil samples by using pH and dye based method. Various physical and chemical parameters were optimized under submerged fermentation for Lasparaginase production. Maximum productivity of L-asparaginase (19.5 U/ml) was achieved by employing medium containing 2% (w/v) Lasparagine as substrate concentration, 1%(w/v) glucose as carbon source, 1% (w/v) ammonium sulphate as an additional nitrogen source with the incubation period of 96 h and incubation temperature at 30°C, initial pH 6.5 at an inoculum level 20% (v/v) with 48 h old inoculum was found to be optimum for maximum yield.Keywords
L-Asparaginase, Optimization and Submerged Fermentation.- Synthesis of Linear Antenna Arrays Using Evolutionary Algorithms
Abstract Views :163 |
PDF Views:4
Authors
Affiliations
1 Department of ECE, GITAM University, Visakhapatnam – 45, IN
2 Department of ECE, AU College of Engineering, Andhra University, Visakhapatnam - 03, IN
1 Department of ECE, GITAM University, Visakhapatnam – 45, IN
2 Department of ECE, AU College of Engineering, Andhra University, Visakhapatnam - 03, IN
Source
Wireless Communication, Vol 9, No 4 (2017), Pagination: 71-76Abstract
Pattern Synthesis is one of the important problems in all communication systems including radars. The beams with narrow beamwidth and less side lobe level are very useful in point to point communication. Most often patterns are designed using conventional design techniques. However, most of them do not yield optimized and desired patterns. In view of all these facts, intensive investigations are carried out thoroughly on the pattern synthesis techniques with the objective of obtaining narrow beams with low sidelobes from linear arrays using different novel evolutionary algorithms. The Linear Antenna Array with Dipole radiators is practical antenna array to scan the entire azimuthal plane. Hence different Optimization techniques are applied on this Linear Antenna Array. Later thinning process is applied on the optimized array for better results. An attempt is made to compare Optimized thinned array and uniformly distributed fully populated array. The results are found to be very much effective which can be used for different wireless communication applications.
Keywords
Sidelobe Level, Narrow Beams, Optimization, BAT Algorithm, Thinning.- Design and Performance of Resonant Spacing Linear Patch Array with Mitered Bend Feed Network for Wireless Applications
Abstract Views :134 |
PDF Views:0
Authors
Affiliations
1 Department of Electronics and Communication Engineering, DVR and Dr. HS MIC College of Technology, Kanchikacherla –521180, Andhra Pradesh, IN
2 Department of Electronics and Communication Engineering, Andhra University College of Engineering (AUCE), Visakhapatnam – 530003, Andhra Pradesh, IN
3 Department of Electronics and Communication Engineering, Maharaj Vijayaram Gajapathi Raj (MVGR) College of Engineering (Autonomous), Vizianagaram – 535005, Andhra Pradesh, IN
1 Department of Electronics and Communication Engineering, DVR and Dr. HS MIC College of Technology, Kanchikacherla –521180, Andhra Pradesh, IN
2 Department of Electronics and Communication Engineering, Andhra University College of Engineering (AUCE), Visakhapatnam – 530003, Andhra Pradesh, IN
3 Department of Electronics and Communication Engineering, Maharaj Vijayaram Gajapathi Raj (MVGR) College of Engineering (Autonomous), Vizianagaram – 535005, Andhra Pradesh, IN
Source
Indian Journal of Science and Technology, Vol 10, No 31 (2017), Pagination:Abstract
Objective: This research paper focuses on the simulated design and its analysis of 2 element microstrip patch antenna arrays with Quarter wave transformer feed and mitered bend feed network that is widely used in ISM frequency bands in the field of wireless communications. Methods: Various types of microstrip array antennas using Quarter wave transformer feed and with miter bend feeds are designed using HFSS 13.0 and fabricated by photolithography technique using FR-4 substrate, which is tested using VNA E5071C. Findings: The optimum performance of the feeding system is based on various antenna parameters. Here 1X2 array antennas are designed. Miter bends are used for better impedance matching. Usage of miter bends declines the reflection coefficient. There is improvement in gain by using miter bend feed network. Applications: Good impedance matching, optimum reflection coefficient and high gain are achieved by metered bends. The obtained results show that the designed antenna is an apt tool for communications.Keywords
Corporate Feed, HFSS, Microstrip Antenna, Mitered-Bend Feed, Quarter-Wave Feed Transformer, Reflection Coefficient, WLANFull Text