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Venkateswara Rao, N.
- CPW-Fed Compact Ultra Wideband MIMO Antenna for Portable Devices
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Authors
Affiliations
1 Department of ECE, K L University, Guntur - 522502, Andhra Pradesh, IN
2 Department of ECE, Bapatla Engineering College, Guntur - 522101, Andhra Pradesh, IN
1 Department of ECE, K L University, Guntur - 522502, Andhra Pradesh, IN
2 Department of ECE, Bapatla Engineering College, Guntur - 522101, Andhra Pradesh, IN
Source
Indian Journal of Science and Technology, Vol 9, No 17 (2016), Pagination:Abstract
Background/Objectives: A novel Coplanar Waveguide (CPW) fed Multiple Input Multiple Output (MIMO) ultrawideband (UWB) antenna with a size of 26mm x 40mm x 0.8mm is proposed for portable device applications. Methods/Statistical Analysis: Two monopole elements with CPW fed are the elements of MIMO antenna and are placed perpendicular to each other to obtain pattern diversity. To enhance the isolation between elements and to improve impedance bandwidth, a long protruding ground stub is etched on the ground plane. Findings: The proposed antenna can cover the frequency band from 2.3-12.5 GHz with isolation more than -20 dB over the entire frequency band. A peak realized gain of 4.5 dBi and efficiency of more than 90% is achieved through the proposed antenna model. Applications/Improvements: High isolation of more than -20 dB is obtained from 2.3-12.5 GHz. The proposed antenna is good candidate for portable device applications.Keywords
Compact, Coplanar Waveguide (CPW) Feed, Multiple Input Multiple Output Antenna (MIMO), Mutual Coupling, Ultra Wideband (UWB).Full Text
- On a Paper of Andre Schlnzfel
Abstract Views :173 |
PDF Views:0
Authors
Affiliations
1 Department of Mathematics, Andhra University, Waltair, IN
1 Department of Mathematics, Andhra University, Waltair, IN
Source
The Journal of the Indian Mathematical Society, Vol 29, No 4 (1965), Pagination: 165-167Abstract
Andre Schinzel [1] proved that the equation 3/(2n + 1) = 1/x + l/y + 1/z is solvable for any fixed integer n > 1 in three distinct odd positive integers x, y. z. Here our object is to specify certain distinct odd positive integral solutions for the above equation and to discuss the solvability.
- Characterization of Clad Joints of High Strength Low Alloy Steel with Stainless Steel and Titanium
Abstract Views :338 |
PDF Views:4
Authors
Affiliations
1 Defence Metallurgical Research Laboratory, Kanchanbagh PO, Hyderabad-500058, IN
1 Defence Metallurgical Research Laboratory, Kanchanbagh PO, Hyderabad-500058, IN
Source
Indian Welding Journal, Vol 51, No 4 (2018), Pagination: 46-56Abstract
In the present investigation, a study has been carried out to understand the structure-property correlations in explosive clad joints of high strength low alloy steel (Yield Strength >600 MPa) in as-clad, hot rolled and heat treated conditions. The cladding materials employed were austenitic stainless steel of AISI 347 grade and commercial pure (CP) titanium. An attempt has also been made to realise the structure-property correlations in the clad joint of the HSLA steel with AISI 347 grade austenitic stainless steel produced by weld overlay cladding technique. In explosive cladding, the interface was found to be wavy type and in weld overlay cladding, the interface was flat. Explosive clad joints of HSLA steel + austenitic stainless steel exhibited a bond strength of 491 MPa in as-clad condition and 408 MPa after hot rolling and heat treatment. Explosive clad joint of HSLA steel + CP titanium exhibited a bond strength of 356 MPa in as-clad condition as CP titanium possesses lower strength (337 MPa) compared to that of AISI 347 grade austenitic stainless steel (515 MPa). The weld overlay clad joint exhibited a bond strength of 488 MPa which is almost equal to that of explosive clad joint in as-clad condition. The clad joints of austenitic stainless steel and CP titanium, with the base plate in heat treated condition, exhibited good formability when three point bend tests were conducted upto 114º and 139º respectively.Keywords
Explosive Cladding, Weld Overlay Cladding, Hsla Steel, Stainless Steel, Microstructure, Shear Bond Strength.References
- Narayanadas J (2012); Naval materials for lndian defence applications, IIM Metal News-Special Issue on Defence Materials,15, 2, pp. 20-27.
- Malakondaiah G, Srinivas M and Balamuralikrishnan R (2012); High performance steels for Indian defence, IIM Metal News-Special Issue on Defence Materials, 15, 2, pp. 28-31.
- ASTM E 8, (2004); Standard test methods for tension testing of metallic materials, Annual book of ASTM standards-2004, ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA.
- Crossland B and Bahrani BS, (1981); Fundamentals of explosive welding, Source Book on Innovative Welding Processes, ASM, Metals Park, Ohio, pp. 99-115.
- Cowan GR, Bergmann OR and Holtzman AH (1971); Metallurgical Transactions, 2A, pp. 3145 -3155.
- Mamalis AG, Szalay A, Vaxevanidis NM and Pantelis DI, (1994); Materials Science and Engineering, A188, 267-275.
- Nobili A, Masri T and Lafont M C (1999); in Proc Reactive Metals in Corrosive Applications Conference, ATI Wah Chang, Albany, OR, USA, pp. 89-98.
- Kacar R and Acarer M, (2003); Microstructure–property relationship in explosively welded duplex stainless steel–steel, Materials Science and Engineering: A, 363, pp. 290-96.
- Nobili A (1998); Stainless Steel World, 10, pp. 33-37.
- Holtzmann AH and Cowan GR (1965); American Welding Society, Welding Research Council Bulletin, 104, pp.1-40.
- Kamachi MU, Ananda Rao B M, Shanmugam K, Natarajan R and Baldev Raj (2003); Corrosion and microstructural aspects of dissimilar joints of titanium and type 304L stainless steel, Journal of Nuclear Materials, 321, pp. 40-48.
- Nizamettin Kahraman, Behcet Gulenc and Fehim Findik, (2005); Joining of titanium/stainless steel by explosive welding and effect on interface, Journal of Materials Processing Technology, 169, pp. 127-133.
- Song J, Kostka A, Veehmayer M and Raabe D (2011); Hierarchical microstructure of explosive joints: Example of titanium to steel cladding, Materials Science and Engineering: A, 528, pp. 2641-47.
- Venkateswara Rao N, Sarma DS, Nagarjuna S and Madhusudhan Reddy G (2009); Influence of hot rolling and heat treatment on structure and properties of HSLA steel explosively clad with austenitic stainless steels', Material Science and Technology, 25, pp. 1387-1396.