The Experts below are selected from a list of 57423 Experts worldwide ranked by ideXlab platform
Varadharajan Sridhar - One of the best experts on this subject based on the ideXlab platform.
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the dynamics of spectrum management legacy technology and economics
2014Co-Authors: Rohit Prasad, Varadharajan SridharAbstract:Even as spectrum management regimes are moving from a command and control regime to a flexible use regime, new Technological developments are suggesting that there are significant opportunities in managing large swathes of spectrum as a common property resource, in addition to flexible use. The demand for spectrum has never been so acute as today's communication services extend beyond simple voice to complex data and video, augmented by evolving technologies such as peer-to-peer sharing, social networking, Fourth and Fifth Generation networks, Big Data, and cloud computing. On the other hand, supply of spectrum is restricted due to competing nature of uses and vested interests of incumbent holders. Political legacies and market realities in different regimes pose unique challenges for spectrum managers who must negotiate a tricky path to the land promised by Technological Possibility. With case studies from early adopters of mobile technology and an in-depth exploration of the Indian case, this book presents a pragmatic and modern approach for spectrum managers to get from where they are to where they can be. This book covers the theoretical framework governing technology, and economics of spectrum. Examples derived from practices around the world are given to illustrate the underlying principles. Future technologies that enable use of spectrum spaces that have so far not been used are documented along with accompanying economic rationale and policy prescriptions. The significant addition in this book is the illustration of the migration from the command and control regime of spectrum allocation to flexible methods and further towards the spectrum of the commons. The regulatory and policy implications are discussed, drawing parallels to practices around the world. The second part of the book is devoted to the spectrum management and policies in India, starting from the initial allocation in 1995 to the substantial controversies surrounding the first-come, first serve principle practiced during 2000s, to finally liberalization and auction of spectrum in 2012-13. The chapter on broadcast spectrum discusses the developments relating to digitization of terrestrial and satellite broadcasting and its implications for mobile services, including the release of digital dividend spectrum.
Indradev Samajdar - One of the best experts on this subject based on the ideXlab platform.
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Composition Gradient and Particle Deformed Zone: An Emerging Correlation
Metallurgical and Materials Transactions A, 2019Co-Authors: Aditya Prakash, Tawqeer Nasir Tak, Arijit Lodh, Niraj Nayan, S. V. S. Narayana Murty, P. J. Guruprasad, Indradev SamajdarAbstract:Compressive ductility of the as-cast AA7075 was nearly doubled by hot compression and by appropriate homogenization treatment. The latter dissolved the 2nd phase, and introduced compositional gradients around the ‘surviving’ precipitates. Direct observations, through split channel die compression, revealed a correlation between particle deformed zone (PDZ: deformed aluminum matrix surrounding coarse 2nd phase particle), the composition gradient and the working temperature. Local misorientation in the PDZ reduced, remarkably, with the introduction of composition gradient and higher working temperature. The generation of PDZ, especially the influence of the composition gradient and the working temperature, was modeled successfully with discrete dislocation dynamics (DDD). More importantly, tailoring the composition gradients around the second phase brought out clear Technological Possibility of improving the as-cast compressive ductility without sacrificing the particle content and the compressive strength.
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Microstructural Engineering in Eutectoid Steel: A Technological Possibility?
Metallurgical and Materials Transactions A, 2018Co-Authors: A. Durgaprasad, S. Giri, S. Lenka, Saurabh Kundu, Sanjay Chandra, Sushil Mishra, Roger D. Doherty, Indradev SamajdarAbstract:Eutectoid wire rods were subjected to controlled thermo-mechanical processing (TMP). Both increased cooling rate and applied stress during the austenite-to-pearlite decomposition produced significant changes in the microstructure: major increases in the pearlite’s axial alignment and minor decreases in the interlamellar spacing. The pearlite alignment was correlated with changes in the ferrite crystallographic texture and the state of residual stress. Microstructural engineering, improved axial alignment of pearlite, through controlled TMP gave a fourfold increase in torsional ductility. TMP of eutectoid steel thus appears to have interesting Technological possibilities.
Rohit Prasad - One of the best experts on this subject based on the ideXlab platform.
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the dynamics of spectrum management legacy technology and economics
2014Co-Authors: Rohit Prasad, Varadharajan SridharAbstract:Even as spectrum management regimes are moving from a command and control regime to a flexible use regime, new Technological developments are suggesting that there are significant opportunities in managing large swathes of spectrum as a common property resource, in addition to flexible use. The demand for spectrum has never been so acute as today's communication services extend beyond simple voice to complex data and video, augmented by evolving technologies such as peer-to-peer sharing, social networking, Fourth and Fifth Generation networks, Big Data, and cloud computing. On the other hand, supply of spectrum is restricted due to competing nature of uses and vested interests of incumbent holders. Political legacies and market realities in different regimes pose unique challenges for spectrum managers who must negotiate a tricky path to the land promised by Technological Possibility. With case studies from early adopters of mobile technology and an in-depth exploration of the Indian case, this book presents a pragmatic and modern approach for spectrum managers to get from where they are to where they can be. This book covers the theoretical framework governing technology, and economics of spectrum. Examples derived from practices around the world are given to illustrate the underlying principles. Future technologies that enable use of spectrum spaces that have so far not been used are documented along with accompanying economic rationale and policy prescriptions. The significant addition in this book is the illustration of the migration from the command and control regime of spectrum allocation to flexible methods and further towards the spectrum of the commons. The regulatory and policy implications are discussed, drawing parallels to practices around the world. The second part of the book is devoted to the spectrum management and policies in India, starting from the initial allocation in 1995 to the substantial controversies surrounding the first-come, first serve principle practiced during 2000s, to finally liberalization and auction of spectrum in 2012-13. The chapter on broadcast spectrum discusses the developments relating to digitization of terrestrial and satellite broadcasting and its implications for mobile services, including the release of digital dividend spectrum.
A. Durgaprasad - One of the best experts on this subject based on the ideXlab platform.
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Microstructural Engineering in Eutectoid Steel: A Technological Possibility?
Metallurgical and Materials Transactions A, 2018Co-Authors: A. Durgaprasad, S. Giri, S. Lenka, Saurabh Kundu, Sanjay Chandra, Sushil Mishra, Roger D. Doherty, Indradev SamajdarAbstract:Eutectoid wire rods were subjected to controlled thermo-mechanical processing (TMP). Both increased cooling rate and applied stress during the austenite-to-pearlite decomposition produced significant changes in the microstructure: major increases in the pearlite’s axial alignment and minor decreases in the interlamellar spacing. The pearlite alignment was correlated with changes in the ferrite crystallographic texture and the state of residual stress. Microstructural engineering, improved axial alignment of pearlite, through controlled TMP gave a fourfold increase in torsional ductility. TMP of eutectoid steel thus appears to have interesting Technological possibilities.
Matyukhina A. - One of the best experts on this subject based on the ideXlab platform.
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Technological possibilities of using natural gas in shaft furnaces for limestone roasting
'National University of Science and Technology MISiS', 2020Co-Authors: Matyukhin V., Yaroshenko Y. G., Zhuravlev S. Y., Morozova E., Matyukhina A.Abstract:One of the ways to improve the technology of limestone roasting in shaft furnaces is associated with improvement of conditions of combustion with natural gas when burning it directly in the layer. To implement this technology, it is necessary to ensure the development of two parallel processes: preparatory, in which the initial gas-air mixture is formed and heated to the ignition temperature, and the main one, during which a layer of combustion of gaseous fuel occurs. At air-blast tuyere feed and at coaxial jet supply of gaseous fuel under increased pressure when there are gas permeable nozzles in the path, a more powerful gas flow (natural gas) flows out of the nozzle at high speed into the external environment. It creates conditions for air flow ejection. Inside the annular space between the streams, a combustion zone is formed, on the inner and outer side of which there are circulating vortices directed along the axis of the jet to the nozzle. It improves stability of the gas-air mixture ignition. The considerable range of turbulent jets (at elevated pressures of the gaseous medium), as well as the Possibility of sufficient complete mixing in the boundary layer, opens up the Possibility of forming a gas-air mixture of a given composition along the front of the flare process, the movement of gas jets. To ignite the gas flow in the layer, it is necessary to ensure its preheating at least to a temperature of 800-1050 °C using a heat source located near its entrance. Energy efficiency of this direction is confirmed by experimental studies on a shaft furnace with a working space with diameter of 3 m. According to the results of experimental sounding of the heated zone of a limestone shaft furnace (in the mode of layer burning of natural gas), regularities were established in changing the temperature field of the burning layer with the formation of maximum temperature of 1200 °C at a distance of 200mm from the nozzle section. The depth of formation of the combustion zone was limited to the level of 110mm with the spread of the region of high temperatures over a distance of up to 1000 mm. Technological Possibility of forming a region of high temperatures of 1100-1600 °C with a length of the high-temperature zone up to 2000mm was established. © 2020 National University of Science and Technology MISIS. All rights reserved
