226 research outputs found
Investigating MapReduce framework extensions for efficient processing of geographically scattered datasets
No full textWe observe two important trends brought about by the evolution of Internet in recent years. Firstly to improve end-to-end application performance in presence of bottlenecks in the wide-area Internet communication, modern day Internet services are designed in a decentralized fashion involving geographically distributed data-centers connected through the Internet. Secondly the pervasive nature of Internet services has resulted into an exponential growth in the size of digital information created, captured or replicated. Organizations are keenly interested in mining this information to uncover trends, statistics and other actionable information which can give them competitive advantage. These two trends necessitate the design of a large-scale data processing system which can operate efficiently in a distributed environment involving multiple datacenters connected through the Internet. In recent years, MapReduce programming model and specifically its open source implementation Hadoop is gaining a lot of traction for performing large-scale data processing in a centralized environment. Our evaluation of different real-world usage scenarios of Hadoop deployments revealed that the organizations with the distributed datasets are required to copy the entire dataset to a centralized location so that it can be efficiently processed by the Hadoop MapReduce framework. As the Internet evolves growth in the size of distributed datasets would outpace the improvements in the network bandwidth available in the Internet. At that point the approach of copying the entire dataset to a single location using Internet would become infeasible. In this thesis, we have investigated the possibility of extending the MapReduce and specifically Hadoop framework to operate in a distributed environment involving multiple datacenters connected through the Internet. We also have proposed policies to improve the performance of Hadoop MapReduce framework in a distributed environment. We have observed that our policies improve the performance of Hadoop framework substantially.M.S.Includes bibliographical referencesby Hrishikesh Gadr
Framework for crawling and local event detection using twitter data
No full textTwitter is a popular social media service, with millions of registered users as of December 2010. Twitter hosts substantial amounts of user-contributed data of real-world events. Twitter‟s core functions represent a simple social awareness stream model. Twitter users share information about upcoming events, the events the users are attending and events being broadcasted. The users also specify their location in their profile on Twitter. We can programmatically collect data from Twitter using their API and detect top terms and events in the data. Researchers can use this program to collect any kind of data from social networks easily. Journalists can get a real time the list of events detected by this method. In this thesis, we propose a solution to tackle the problem above. We wrote scripts that collected Twitter data through Twitter API. The scripts collect data according to user location and by search keywords. We built a web interface that provides mechanism to manage the collection of data. The web interface allows addition of new locations and keywords to the data collection. We collected Twitter data for important locations across the United States of America and the world using these tools. We use two approaches to detect trends in the data. In the first approach, we detected spikes in data by looking at overall rate of tweets at each location over a period of time. In the second approach, .we indexed the data according to location and time of the day. Then, we identified trends in the indexed data by ranking the terms according to spikes in term frequency. Using our framework, we can detect the top events and trends for a given time period and location according to Twitter data.M.S.Includes bibliographical referencesby Hrishikesh Baksh
First record of the heart urchin Metalia persica (Mortensen, 1940) (Spatangoida: Brissidae) from the Chennai coast, India
No full textKanagaraj, Chamundeeswari, Mooi, Rich, Kumar, Deepak Samuel Vijay, Premachandran, Hrishikesh, Rajendran, Abhilash Kottarathil, Rethinavelu, Sankar, Ramachandran, Purvaja, Ramachandran, Ramesh (2019): First record of the heart urchin Metalia persica (Mortensen, 1940) (Spatangoida: Brissidae) from the Chennai coast, India. Zootaxa 4624 (2): 296-300, DOI: 10.11646/zootaxa.4624.2.1
Bollywood cinema: A critical genealogy
No full text"Bollywood" has finally made it to the Oxford English Dictionary. The 2005 edition defines it as: "a name for the Indian popular film industry, based in Bombay. Origin 1970s. Blend of Bombay and Hollywood." The incorporation of the word in the OED acknowledges the strength of a film industry which, with the coming of sound in 1931, has produced some 9,000 films. (This must not be confused with the output of Indian cinema generally, which would be four times more). What is less evident from the OED definition is the way in which the word has acquired its current meaning and has displaced its earlier descriptors (Bombay Cinema, Indian Popular Cinema, Hindi Cinema), functioning, perhaps even horrifyingly, as an "empty signifier" (Prasad) that may be variously used for a reading of popular Indian cinema. The triumph of the term (over the others) is nothing less than spectacular and indicates, furthermore, the growing global sweep of this cinema not just as cinema qua cinema but as cinema qua social effects and national cultural coding. Although Indian film producers in particular, and pockets of Indian spectators generally, continue to feel uneasy with it (the vernacular press came around to using "Bollywood" only reluctantly), its ascendancy has been such that Bombay Dreams (the Andrew Lloyd Weber musical) and the homegrown Merchants of Bollywood both become signifiers of a cultural logic which transcends cinema and is a global marker of Indian modernity. As the Melbourne (March 2006) closing ceremony of the Commonwealth Games showed, Bollywood will be the cultural practice through which Indian national culture will be projected when the games are held in Delhi in 2010. International games (the Olympics, World Cup Soccer, Asian Games, Commonwealth Games, and so on) are often expressions of a nation's own emerging modernity. For India that modernity, in the realm of culture, is increasingly being interpellated by Bollywood
TIN OXIDE MODIFIED SILICON NANOWIRES ON SILICON CHIP AS AMMONIA SENSOR
No full textTitle: TIN OXIDE MODIFIED SILICON NANOWIRES ON SILICON CHIP AS AMMONIA SENSOR
Authors: Saravanan Yuvaraja1,2, Hrishikesh Dhasmana2, Amit Kumar2, Vivek Kumar2, Abhishek Verma2, V. K. Jain2 and Khaled Salama1.
Section 1: HOW YOU ARE EXPOSED TO AMMONIA ?
Section 2: HOW AMMONIA AFFECTS YOUR HEALTH ?
Section 3: WE CAN SAVE YOU FROM AMMONIA EXPOSURE
Level 1: Synthesis
Level 2: Performance analysis
Level 3: Prototype demonstration
Attention: Both Synthesis process flow and Gas sensing mechanism concept of the reported device architecture is presented in the vide
High mobility organic field-effect transistors based on defect-free regioregular poly(3-hexylthiophene-2,5-diyl)
No full textWe report on organic field-effect transistors (OFETs) prepared using defect free (100% regioregular) poly(3-hexylthiophene-2,5-diyl) (DF-P3HT) as semiconductor and cross-linked poly(vinyl alcohol) (cr-PVA) as gate insulator. High field-effect mobility (μFET) of 1.2 cm2 V−1 s−1 is obtained and attributed to the absence of regioregularity defects. These transistors have transconductance of 0.35 μS and the DF-P3HT film shows larger crystallites (∼80 Å) than a highly regioregular (>98%) material (∼32 Å). Devices with increased μFET (2.8 cm2 V−1 s−1) could be obtained at the expense of the On-Off current ratio, which was reduced by one order of magnitude, when poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) treatment was applied to the dielectric surface. Our results suggest that the interaction of charged sites at the dielectric surface with regioregularity defects of the P3HT is an important factor degrading μFET even at very low concentration of regioregularity defects
Structural and optical behavior of thin films of protein (BSA)-Polyelectrolyte (PAA, PSS) complexes
No full textRole of Arbuscular Mycorrhiza in Heavy Metal Tolerance in Plants: Prospects for Phytoremidiation
No full textArbuscular Mycorrhiza (AM) is an obligate biotroph, which mainly improves phosphorus nutrition, ability to withstand water stress and offers a natural potential for biological control of root pathogen. They are also reported to be present on the roots of plants growing on metal-contaminated soils and play an important role in metal tolerance and accumulation. Isolation of the heavy metal tolerant AM fungi can be a potential biotechnological tool for inoculation of plants for successful phytoremediation. AM fungi provide an attractive system to advance plant-based environmental clean-up. During symbiotic interaction the hyphal network functionally extends the root system of their hosts. Thus, plants in symbiosis with AM fungi have the potential to take up heavy metal (HM) from an enlarged soil volume. This review throws light on the potential and the prospects of AM fungi in heavy metal tolerance of plant and its utilization for enhancing phytoremediation of heavy metal contaminated soils.Key words: Arbuscular Mycorrhiza (AM), Heavy metal, Phytoremediation Hrishikesh Upadhyaya et al. Role of Arbuscular Mycorrhiza in Heavy Metal Tolerance in Plants: Prospects for Phytoremidiation. J Phytol 2/7 (2010) 16-27
Numerical Study On The Impact Of Self Induced Gravity Waves On Offshore Wind Farms
No full textThe present work studies the impact of self-induced Atmospheric Gravity Waves (AGWs) excited by an moderately sized offshore wind farm immersed in a Conventionally Neutral Boundary Layer (CNBL). A wind farm of finite span-wise length, consisting of 25 NREL 15MW wind turbines laid out in (5 X 5 Aligned manner) is considered. In order to achieve the same, two customized open source CFD RANS solvers are used, based on the OpenFOAM and SOWFA environments. The study primarily focuses on the impact of thermal stratification in the Free Atmosphere, the strength of the capping inversion and height of the same on the characteristics of the AGWs excited. Further, the work also evaluates the impact of the excited AGWs on the wind farm in the form of velocity deficits at each individual turbine column and also power down the analysis.The study finds that for a higher capping inversion strength, the AGWs excited by the wind farms are trapped and propagate horizontally along the capping inversion along with its vertically propagating counterpart. These cause velocity fluctuations at the hub height of the turbine, which results in AGW induced wind farm blockage that lowers the amount of incoming kinetic energy at the first turbine row and an increased velocity at the last two rows. Furthermore, the trapped AGWs cause the collective wake of the wind farm to recover faster. Moreover, the study proves that the height of the capping inversion determines the extent of AGW excitation by the wind farm. It was found lower capping inversion heights led to a higher AGW excitation and higher AGW induced flow blockage and wake recovery. Lastly, the study also finds that the thermal stratification in the Free Atmosphere determines the vertical wavelength of the AGWs propagating in the free atmosphere. Furthermore, the study also reports that for a higher Free Atmosphere stratification, a lower AGW induced blockage is observed.Aerospace Engineerin
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