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August 31, 2019
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Jinni Semantic Search for Movies

first_img Citation: Jinni: Semantic Search for Movies (2009, July 1) retrieved 18 August 2019 from https://phys.org/news/2009-07-jinni-semantic-movies.html (PhysOrg.com) — One of the most interesting things I have come across over the Internet is the movie search engine Jinni. Can’t think of anything to watch tonight? Type in a phrase, and dozens of moves appear in an attractive visual search result. Of course, if you want to see movies that match your tastes and preferences, you will have to set up a profile and become a part of the The Movie Genome. Jinni has been called “the Pandora of music” for good reason. Because of the ability to compare tastes to others and rank movies according to your preference, Jinni seems like a social network at first glance. However, the people behind Jinni make it clear that it is an “Internet application designed to fit how people relate to movies and TV.” As with all applications of this nature, the more you use it, the more accurate your results will become over time. I compared Jinni to the recommendation I get from Netflix, and found that Jinni offers something much more sophisticated. There’s a reason that CNET thinks that Jinni is hands down the best movie recommendation engine available.The real cool feature, though, is the semantic search. Type in searches according to plots, genre and/or actors. You can even search using your mood as a guide. You can type in nearly any search phrase and something will come up. If you are confused about the connections between some of the movies that appear, you can click on a button that will tell why the movies are “related”. Jinni uses a proprietary algorithms to do a lot of the work, but the staff has done a great deal of manual tagging. Automatic tagging continues as Jinni “learns” more about different movies.My favorite thing about Jinni, though, is the fact that it reminds me of old favorites not thought of in years — and introduces me to interesting new movie possibilities.© 2009 PhysOrg.com Jinni offers semantic search for movies. Explore further Study: ‘Chick flicks’ also enjoyed by men This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

August 31, 2019
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Borexino experiment detects geoneutrinos

first_img Explore further Citation: Borexino experiment detects geo-neutrinos (2010, March 16) retrieved 18 August 2019 from https://phys.org/news/2010-03-borexino-geo-neutrinos.html © 2010 PhysOrg.com In the current two-year study, named the Borexino experiment, there were no strong background signals because the nearest nuclear reactor is hundreds of kilometers away. The detector, photomultiplier tubes and liquids used were also specifically chosen because of their low levels of intrinsic radioactivity.The aim of the Borexino experiment was to detect low-energy solar neutrinos in a detector comprising 300 tonnes of pseudocumene, a doped hydrocarbon fluid, encased inside a nylon sphere. The sphere was encased inside a stainless steel sphere containing 1,000 tonnes of pseudocumene and lined with 2,200 photo-sensors capable of detecting single photons of light. The steel sphere was suspended in an 18 meter diameter steel tank containing 2,400 tonnes of highly purified water. During the experiment, 9.9 geo-neutrino events were detected, with uncertainties of +4.1 and -3.4. One of the researchers, Professor Gianpaolo Bellini from the University of Milan, said the results rule out the hypothesis that most of the planet’s internal heat is generated by a uranium-fuelled nuclear geo-reactor in the Earth’s core.Several larger experiments are being planned, including one in which a 10,000 tonne detector would be built on the bottom of the Pacific Ocean, where the Earth’s crust is very thin. Professor Bellini said the experiment marks the start of a new era in the study of Earth’s interior. New results confirm standard neutrino theory Neutrinos are extremely inert, chargeless, fundamental particles of almost zero mass that are emitted by the Sun and created by cosmic rays arriving on Earth. They have been the subject of research for many years, and studies of them have increased our knowledge of the physics of the Sun.Geo-neutrinos are electron antineutrinos that are created inside the Earth when radioactive nuclei of elements such as thorium and uranium decay. Measurements of the flux of geo-neutrinos may help scientists understand how much of the Earth’s internal heat is caused by radioactive decays, and this could increase our understanding of processes arising from convection currents within the mantle that affect movements of the tectonic plates and volcanic activity.Detecting any kind of neutrino is difficult since huge volumes of detector material must be used, and the detector must be deep underground to avoid interference from cosmic rays. Solar and atmospheric neutrinos can be studied by their interactions with heavy water nuclei, but signals from geo-neutrinos would be swamped by the radioactivity in the heavy water, and so the researchers used hydrocarbon materials instead. A geo-neutrino passing through the hydrocarbon can collide with a proton to create a neutron and positron, and this collision generates a dual gamma-ray emission and small burst of detectable light.Geo-neutrinos were first detected by Japanese researchers in 2005 during a project known as the KamLAND experiment. Their detector was in a mine one kilometer underground, and was located close to several nuclear reactors, since the team was studying reactor antineutrinos. They had to separate the geo-neutrino signals from the stronger antineutrino emissions from the reactors. — The group’s paper will be published in the Europhysics Letters B and is available on Arxiv website.– Borexino Experiment: borex.lngs.infn.it/ (PhysOrg.com) — The Borexino collaboration of about 80 scientists from six countries, who have been working with a detector buried 1.5 km beneath the Gran Sasso mountain near l’Aquila in Italy have detected geo-neutrinos, which are electron antineutrinos created by radioactive decays inside the Earth’s mantle and crust. More information: View of the Borexino “Stainless Steel Sphere” (SSS) from from the “Water Tank”, before cables and PMTs installation. PausePlay% buffered00:0000:00UnmuteMuteDisable captionsEnable captionsSettingsCaptionsDisabledQuality0SpeedNormalCaptionsGo back to previous menuQualityGo back to previous menuSpeedGo back to previous menu0.5×0.75×Normal1.25×1.5×1.75×2×Exit fullscreenEnter fullscreen Play Borexino vessel installation (View from the Borexino CCD cameras) This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

August 31, 2019
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Japan plans to build robot moon base by 2020

first_img(PhysOrg.com) — Believing that a moon base is essential for exploration of the solar system, Japan has recently announced plans to send humanoid robots to the moon to construct a robot lunar base. As part of the $2.2 billion project, the robots will begin surveying the moon around 2015, and then build the unmanned base near the moon’s South Pole by 2020. An illustration of Japan’s proposed robot moon base. Credit: JAXA. A Japanese government panel chaired by Katsuhiko Shirai, President of Waseda University, has developed a rough outline of the project. First, the robots, weighing about 660 pounds each, will begin by surveying the moon, taking images of the surface, collecting rocks, and returning the rocks to Earth via rocket for seismographic research. Later, robots will be sent to the moon to construct the lunar base for themselves.According to the government panel, the robots and the unmanned moon base will be powered by solar panels. The robots will be controlled from Earth, but will also have a high degree of autonomy that enables them to operate on their own to perform certain tasks. Ultimately, the base could serve as a starting point for future robot colonizers, and even human colonizers. © 2010 PhysOrg.com Citation: Japan plans to build robot moon base by 2020 (2010, May 28) retrieved 18 August 2019 from https://phys.org/news/2010-05-japan-robot-moon-base.html Explore further More information: via: CNET United States plans to build lunar base This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

August 31, 2019
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Swimming upstream Flux flow reverses for lattice bosons in a magnetic field

first_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Copyright 2011 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. Sebastian D. Huber in the Department of Condensed Matter Physics at Weizmann, working with Netanel H. Lindner at CalTech’s Institute for Quantum Information and Department of Physics, describes the obstacles encountered in conducting their research. “The Hall conductivity of continuum bosons is directly dictated by the density of particles,” says Huber. “Interesting lattice effects leading to a deviation from this elementary rule are only at work for strong inter-particle interactions. In short, the existence of holes is crucial to our work.” Citation: Swimming upstream: Flux flow reverses for lattice bosons in a magnetic field (2011, December 27) retrieved 18 August 2019 from https://phys.org/news/2011-12-upstream-flux-reverses-lattice-bosons.html Forces acting on a vortex. (a) The classical Magnus force due to the interaction of the velocity field of the vortex and the external flow vs acts perpendicular to vs. (b) Vortex motion leads to a change in the momentum of the system due to its phase singularity, which is perpendicular to its velocity vv. (c) Moving a vortex around a lattice site yields a Berry phase of 2πα = 2π(nb + p). Copyright © PNAS, doi: 10.1073/pnas.1110813108 (PhysOrg.com) — Matter in the subatomic realm is, well, a different matter. In the case of strongly correlated phases of matter, one of the most surprising findings has to do with a phenomenon known as the Hall response – an important theoretical and experimental tool for describing emergent charge carriers in strongly correlated systems, examples of which include high temperature superconductors and the quantum Hall effect. At Weizmann Institute of Science and California Institute of Technology, recent theoretical physics research into bosons interacting in a magnetic field has shown that, among other surprising effects, Hall conductivity – and therefore flux flow – undergo reversal. The scientists have concluded that their findings are immediately applicable to a wide range of phenomena in the realm of condensed matter physics. Concerning the surprising effects they found (e.g., sign reversal) of topological transitions between different integer values, Huber stresses that while it has been well-known since the discovery of the quantum Hall state that topology can have an important influence on solid state systems, there has recently been tremendous interest in topologically non-trivial states in the form of topological insulators. “However,” he adds, “all these systems are characterized by a gap to excitations in the bulk. Our results show that such topological transitions, and consequently the sign-reversals, are possible also in a gapless superfluid.”While these findings are new, they are actually based on a very old theorem by von Neumann and Wigner regarding level crossings. “So,” Huber concludes, “in a sense we only brought existing knowledge on the structure of energy levels into the fascinating new world of topology in condensed matter systems.”center_img Recognizing blood poisoning quickly Explore further While for fermions the band theory of solids together with the Pauli principle provides the notion of holes, for bosons they needed an interaction-driven Mott insulator – a material that should conduct electricity according to conventional band theories, but due to particle-particle interactions is an insulator when measured, particularly at low temperatures – for holes to arise. “Hence, our main challenge was to study a lattice effect in the presence of strong interactions.”Huber and Lindner addressed the question of the Hall conductivity by using concepts of topology like the Chern number and the effective magnetic monopoles which constitute sources of the Chern density. “While these concepts are well known,” Huber explains, “their application to gapless interacting systems is novel. The realization that gapless systems can also have topological transitions like the ones we found between different values of the Chern number, or equivalently, the Hall conductivity, is certainly an exciting new discovery. The actual question we resolved – the value of the Hall coefficient of lattice bosons – has been a longstanding problem motivated by high-temperature superconductivity. In this sense, our work contributes to a deeper understanding of lattice systems in general.”Huber describes the next steps being considered, given that their work has shown that sign reversals of the Hall conductivity are possible in clean systems with no disorder, as well as in a purely bosonic model. “In high-temperature superconductors such reversals are experimentally observed,” Huber notes. ”The common wisdom is that the underlying Fermi surface is undergoing a structural change due to a competing instability of strip-formation. Our work suggests that this might not be the only source of such sign-reversals and no fermionic mechanism needs to be invoked. As the exact nature of these systems is highly controversial, we plan to extend our work to be able to directly access this problem.” More information: Topological transitions for lattice bosons in a magnetic field, Published online before print November 22, PNAS December 13, 2011, vol. 108 no. 50, 19925-19930, doi: 10.1073/pnas.1110813108 Topological transitions in the Bose-Hubbard phase diagram. The Galilean invariant regime denotes the region where σxy is proportional to the particle density nb divided by the magnetic field strength B. Mott insulator lobes are indicated in gray. The yellow and green lines exhibit an emergent particle hole symmetry, where σxy = 0. They are divided into two types: (i) Lines emanating from the tip of the Mott lobe at integer boson filling where σxy has a smooth zero crossing (green). (ii) Transition lines (yellow), through which Bσxy exhibits integer jumps. The latter continue into the phase diagram, with σxy > 0, as indicated by the dashed lines. The blue region corresponds to regions where the Hall conductivity is negative. Copyright © PNAS, doi: 10.1073/pnas.1110813108last_img read more

August 31, 2019
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Suction cup mat based on octopuss suckers developed to build flexible pressure

first_img Citation: Suction cup mat based on octopus’s suckers developed to build flexible pressure sensors (2016, July 6) retrieved 18 August 2019 from https://phys.org/news/2016-07-suction-cup-mat-based-octopus.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Ultra-thin solar cells can bend around a pencil Journal information: Advanced Materials Explore further Schematic representation of microcavity arrays within a octopus-inspired smart adhesive pad. Credit: UNIST Schematic of the fabrication of a smart adhesive pad. Credit: Advanced Materials (2016). DOI: 10.1002/adma.201601407 (Phys.org)—A team of researchers working at South Korea’s National Institute of Science and Technology has found a way to make building flexible pressure sensors easier—by mimicking the suction cups on octopus’s tentacles. In their paper published in the journal Advanced Materials, the researchers describe how they studied the octopus’s parts and then used what they learned to develop a new type of suction based adhesive material. Building flexible sensors, the researchers note, is difficult and cumbersome—it requires moving nano- and/or microribbons of inorganic semiconductor materials onto rubber sheets. Making the process easier, the researchers thought, could be done by building a simple suction device that could hold onto the material and then let go without grabbing it. To build such a device, they turned to the octopus—it gets around, they noted by moving its tentacles to a new location and then holding on using suction cups. The suction cups work due to muscles around their edges that can be made thinner or thicker on demand, increasing or decreasing air pressure inside the cup, allowing for sucking and releasing as desired.To mimic the octopus suction cups, the researchers created a small rubber mat made out of polydimethylsiloxane (a type of silicon that has a rubbery texture) with small pits on one side. At room temperature, the walls of each pit sit in an ‘open’ state, but when the mat is heated to approximately 32°C, the walls contract, creating suction, allowing the entire mate to adhere to a material. To use the mat as a device to move materials, all the team needed to do was heat it, apply to the material, move to the new location, then allow the mat to cool, whereupon the material would be dropped into place.The team reports that the mat worked as envisioned—they made some indium gallium arsenide transistors that sat on a flexible substrate and also used it to move some nanomaterials to a different type of flexible material. They believe there might be a wide variety of applications that could benefit from such mats, such as Band-Aids or sensors that stick to the skin at normal body temperatures but fall off when rinsed under cold water. © 2016 Phys.org More information: Hochan Lee et al. Octopus-Inspired Smart Adhesive Pads for Transfer Printing of Semiconducting Nanomembranes, Advanced Materials (2016). DOI: 10.1002/adma.201601407AbstractBy mimicking muscle actuation to control cavity-pressure-induced adhesion of octopus suckers, smart adhesive pads are developed in which the thermoresponsive actuation of a hydrogel layer on elastomeric microcavity pads enables excellent switchable adhesion in response to a thermal stimulus (maximum adhesive strength: 94 kPa, adhesion switching ratio: ≈293 for temperature change between 22 and 61 °C).Press releaselast_img read more

August 31, 2019
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New property of light discovered

first_imgCredit: CC0 Public Domain A team of researchers affiliated with several institutions in Spain and the U.S. has announced that they have discovered a new property of light—self-torque. In their paper published in the journal Science, the group describes how they happened to spot the new property and possible uses for it. Journal information: Science PausePlay% buffered00:0000:00UnmuteMuteDisable captionsEnable captionsSettingsCaptionsDisabledQuality0SpeedNormalCaptionsGo back to previous menuQualityGo back to previous menuSpeedGo back to previous menu0.5×0.75×Normal1.25×1.5×1.75×2×Exit fullscreenEnter fullscreen More information: Laura Rego et al. Generation of extreme-ultraviolet beams with time-varying orbital angular momentum, Science (2019). DOI: 10.1126/science.aaw9486 Explore further Multicolored light twists in new knotted wayscenter_img Play A new property of light beams, the self-torque of light, which is associated to a temporal variation of the orbital angular momentum. Extreme-ultraviolet ultrafast pulses with self-torque are generated through high harmonic generation. Credit: JILA (USA) Rebecca Jacobson, Servicio de Produccion e Innovacion Digital – Universidad de Salamanca (Spain) The researchers suggest that it should be possible to use their technique to modulate the orbital angular momentum of light in ways very similar to modulating frequencies in communications equipment. This could lead to the development of novel devices that make use of manipulating extremely tiny materials. Scientists have long known about such properties of light as wavelength. More recently, researchers have found that light can also be twisted, a property called angular momentum. Beams with highly structured angular momentum are said to have orbital angular momentum (OAM), and are called vortex beams. They appear as a helix surrounding a common center, and when they strike a flat surface, they appear as doughnut-shaped. In this new effort, the researchers were working with OAM beams when they found the light behaving in a way that had never been seen before.The experiments involved firing two lasers at a cloud of argon gas—doing so forced the beams to overlap, and they joined and were emitted as a single beam from the other side of the argon cloud. The result was a type of vortex beam. The researchers then wondered what would happen if the lasers had different orbital angular momentum and if they were slightly out of sync. This resulted in a beam that looked like a corkscrew with a gradually changing twist. And when the beam struck a flat surface, it looked like a crescent moon. The researchers noted that looked at another way, a single photon at the front of the beam was orbiting around its center more slowly than a photon at the back of the beam. The researchers promptly dubbed the new property self-torque—and not only is it a newly discovered property of light, it is also one that has never even been predicted. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. © 2019 Science X Network Citation: New property of light discovered (2019, June 28) retrieved 18 August 2019 from https://phys.org/news/2019-06-property.htmllast_img read more

August 31, 2019
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The Kids Who Use Tech Seem to Be All Right

first_imgA new paper by scientists at the University of Oxford, published this week in Nature Human Behaviour, should help clear up the confusion. It reveals the pitfalls of the statistical methods scientists have employed and offers a more rigorous alternative. And, importantly, it uses data on more than 350,000 adolescents to show persuasively that, at a population level, technology use has a nearly negligible effect on adolescent psychological well-being, measured in a range of questions addressing depressive symptoms, suicidal ideation, pro-social behavior, peer-relationship problems and the like. Technology use tilts the needle less than half a percent away from feeling emotionally sound. For context, eating potatoes is associated with nearly the same degree of effect and wearing glasses has a more negative impact on adolescent mental health. “This is an incredibly important paper,” says Candice Odgers, a psychologist studying adolescent health and technology at the University of California, Irvine, who wasn’t involved in the research. “It provides a sophisticated set of analyses and is one of the most comprehensive and careful accountings of the associations between digital technologies and well-being to date. And the message from the paper is painstakingly clear: The size of the association documented across these studies is not sufficient or measurable enough to warrant the current levels of panic and fear around this issue.” Read the whole story: Scientific American Such are the conflicting messages about the effects of technology on children’s well-being. Negative findings receive far more attention and have fueled panic among parents and educators. This state of affairs reflects a heated debate among scientists. Studies showing statistically significant negative effects are followed by others revealing positive effects or none at all—sometimes using the same data set.center_img Social media is linked to depression—or not. First-person shooter video games are good for cognition—or they encourage violence. Young people are either more connected—or more isolated than ever.last_img read more

August 31, 2019
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Blood sport and great gamblers

first_imgThe Big Fix (Westland) remains a work of fiction. With his vast experience in reporting and a ring side view of it all, Vikas Singh has captured the drama and the excitement of the contemporary T20 cricket game. Vikas gets the atmosphere of the dugout right to come up with a book that is as riveting and as exciting as a cricket match where the decision is reached only after the last ball.Set in the background of the IPL fiasco, the odds are against an out-of-form captain, Shaurya, to win the championship for his team, Capital Cavaliers, as his coach gets murdered. It has all the on field drama captured very vividly in cricketing terms. The book also shows the other side of big money and sleaze, spot fixing, match fixing, and the damage that  big bucks inflict on sports. It gets one to wonder why the game has gone from sportsmanship to just money making, aboard the gravy train of mega bucks. Also Read – ‘Playing Jojo was emotionally exhausting’The book is easy to read, with 28 chapters full of action-packed sequences. There is the usual rivalry amongst players which gets accentuated in cricket because the difference between selection and rejection is not another chance to play but humongous amount of money. Singh portrays an attitude that has moved beyond the valve system of the captain’s decision, but is also suggestive (through superb one-liners) of a very promiscuous culture that the sportsmen are increasingly exposed to now.    The honey traps,  for dubious reasons, are captured well! A must read for cricket lovers.last_img read more

August 31, 2019
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Dance like no one is watching

first_imgAll you dance enthusiasts step out and grab this chance to experience something more as the Embassy of France in India , Institut Français en Inde and the Alliance Française network brings the second edition of  contemporary dance festival- DanSe DialogueS starting from 11 April.The festival will feature French companies and Franco-Indian collaborations touring 7 cities (Delhi, Mumbai, Chennai, Kolkata, Trivandrum, Hyderabad, and Bengaluru) to present their productions, alongside Indian dance companies. The event will also showcase masterclasses given by choreographers and video screenings of French and Indian dance performances and is slated to end on 29 April. The French Embassy has collaborated with dance professionals throughout the country to organise nation-wideperforming arts festivals. Enlarging its scope to seven cities, the programme is designed to nurture the strong bonds established with India in the field of contemporary dance. Also Read – ‘Playing Jojo was emotionally exhausting’DanSe DialogueS aims to create interest in French and Indian contemporary and alternative dance practices and to participate in the evolution of the Indian contemporary dance scene by fostering exchanges and meetings between professionals of both countries.His Excellency, ambassador of France, Francois Richier said, ‘The exceptional richness of Indian traditional dance justifies that France engages itself more and more in favor of Indo-French collaboration in the field of dance.’  Also Read – Leslie doing new comedy special with NetflixThe first part of the festival consists of two projects for which French choreographers, Mourad Merzouki and David Rolland, worked  with Indian dancers. The second part of the festival aims to showcase the current trends from both the French and Indian dance scene by programming several renowned companies- Xin company with Black Pulp, Retouramont company with Cette immense intimité (Huge intimacy), Julie Nioche Company with Nos solitudes (Our solitudes), Astad Deboo with Rhythm Divine (in Delhi only). The third and last part will consist of four workshops given by choreographers (David Rolland, Astad Deboo, Fabrice Guillot and Julie Nioche) and three screenings of Indian and French dance performances.last_img read more

August 31, 2019
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GSI discovers huge lime mud deposits

first_imgKolkata: In a significant achievement in Marine Mineral Exploration, Geological Survey of India (GSI) has stumbled upon huge lime mud deposits off Gujarat and Maharashtra coast.The officers of GSI’s Marine & Coastal Survey (MCS) Division located at Mangalore has discovered about 72,000 million tonne of lime mud resource, which they feel is a probable solution to the scarcity of high grade limestone in the country.”India has a large resource of limestone on land, but 97 percent of it is of cement grade and only 3 percent is of steel and chemical grade. Our industrial requirement for steel, blast furnace and chemical grade limestone are met from imports. We are hopeful that this discovery will help our country to cut down on imports of limestone for steel, pharmaceutical and other industries,” said Dr Dinesh Gupta, Director General of GSI at a media conference on Thursday. Officials from GSI’s MCS division, located at Mangalore, joined through video conference. Also Read – Rain batters Kolkata, cripples normal lifeThe lime mud resource has been estimated from an area of 6603 sqkm of Arabian Sea with its location at 80-100 km from coast at 55 to 120 m water depth. It may be mentioned that Carbonate rock like limestone and dolomite are important raw materials for the cement, paint, glass and steel industries.Bench scale beneficiation and agglomeration studies carried out at Regional Mineral Processing Laboratory, Indian Bureau of Mines (IBM), Bangalore to understand the industrial utility of offshore lime mud found its suitability for cement and filler industries, flux in blast furnaces in steel plants and steel melting shops. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedDG, GSI also announced the discovery of massive marine sand (construction sand) deposits off Kerala coast.”There is an acute shortage of sand in Kerala and the construction industries in the state are looking for alternative sources. At present, the only alternative available is M-Sand (Manufactured Sand) which is a crushed product of hard rocks. This reserve of good quality sand will immensely benefit construction industry in the state,” a senior GSI official said. More than 745 million tonne of sand has been estimated off Ponnani, Chavakkad, Alleppey and Kollam at four blocks off Kerala coast.last_img read more