Swedish Agency Develops Underwater Wireless Technology

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. Citation: Swedish Agency Develops Underwater Wireless Technology (2007, October 9) retrieved 18 August 2019 from https://phys.org/news/2007-10-swedish-agency-underwater-wireless-technology.html The Swedish Defense Research Agency, FOI has developed an underwater wireless technology that has been tested for accurately predicting weather conditions, sea pollution and earthquakes. The new technology is a vast improvement over traditional echo sound technology.center_img The Swedish Defense Research Agency, FOI employs 800 full time research scientists to develop innovations in technology and research. Its endeavors also include defense and security. The newly developed under water wireless technology was initially developed for military purposes. The technology has been on a trial run sponsored by the European Union to detect environmental changes in the sea.The project manager at FOI states, the utility of the wireless technology is to accurately predict earthquakes, and follow underwater weather patterns. In particular, the technology using sensors at the sea bed will be useful in oil and gas industry exploration. The current echo communications used have limitations. These limitations include a limited data rate in underwater transmissions. The researchers at FOI have discovered a method to reduce the effects of echoes. According to Tommy Oberg, Director of Research at FOI, the improved technology may be used to monitor sea pollution and climate changes. Unmanned underwater vehicles could monitor larger areas of the sea on a 24/7 basis. The new technology is faster in transmitting information and the cost for large scale projects can drastically reduce costs. The new technology is capable of transmitting images, movies and sound. The utility of the new technology is adaptable for security, defense, harbor safety, weather and oil and gas exploration.last_img read more

Proposed test of weak equivalence principle could be most accurate yet

first_img(PhysOrg.com) — The weak equivalence principle (WEP) – which states that all bodies fall at the same rate in a gravitational field, regardless of structure or composition – is one of the key postulates of general relativity. Tests have shown that the WEP is accurate to within one part in 10 trillion, or an uncertainty of 10-13 of the acceleration of gravity. However, a violation of the WEP is suggested by most theories that attempt to unify gravity with the other forces, which is one of the biggest challenges in physics today. Looking for new ways to test the WEP to even greater accuracy and perhaps detect a violation, astrophysicists at the Harvard-Smithsonian Center for Astrophysics have designed a new WEP test to be conducted during free fall in a rocket flight. Copyright 2010 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. “The extreme speed and sensitivity of the tracking frequency laser gauge makes it possible to do this experiment quickly,” Phillips told PhysOrg.com. “A slower or less sensitive measuring device would not allow the experiment to be carried out in the brief time available during a sounding rocket flight.” Reasenberg and Phillips have received support from the Astrophysics Division of NASA to develop both the sounding rocket test and the laser gauge. The sounding rocket will be launched from the NASA Flight Facility at Wallops Island, VA. “A central theme of this experiment’s design is to mitigate systemic errors,” Reasenberg explained. One way this is done is by reversing the orientation of the free-falling experiment between successive pairs of the eight drops. Other design tactics that reduce errors include precisely aligning the lasers to the test mass assemblies using a hexapod motion system (also known as a Stewart platform) and minimizing thermal perturbations to insignificant levels in many ways, such as flying at night to avoid directional solar heating. Although taking all these pains to achieve extreme precision may seem tedious, the scientists do so enthusiastically because the discovery of a WEP violation would have profound implications for physics, astrophysics, and cosmology. For instance, knowledge of a WEP violation would guide the formulation of a theory of gravity to supersede general relativity, which might be a quantum theory of gravity. The quantum theories of gravity being developed now generally predict a violation of the WEP, but most are not yet able to predict the magnitude of the violation. The magnitude of a WEP violation could be within the range of the sounding-rocket experiment, or well below it. Citation: Proposed test of weak equivalence principle could be most accurate yet (2010, May 3) retrieved 18 August 2019 from https://phys.org/news/2010-05-weak-equivalence-principle-accurate.html This illustration shows the two test mass assemblies, which consists of two pairs of aluminum cubes. Four tracking frequency laser gauges measure each cube’s acceleration as it falls to Earth from altitudes of up to 1200 km. Image credit: Reasenberg and Phillips. As astrophysicists Robert Reasenberg and James Phillips explain in a series of papers, their proposed test is aimed at a very small measurement uncertainty of 10-16 after averaging the results of eight separate free fall drops. If the experiment is successful, it would be the most accurate WEP test to date, although it is not the most accurate WEP test that has been proposed: the satellite test of the equivalence principle (STEP) is aimed at a 100-fold smaller measurement uncertainty (10-18). STEP is a proposed cryogenic experiment in an Earth-orbiting spacecraft. One way that scientists can test the WEP is by measuring the accelerations of two bodies made of different materials falling in the same gravitational field. As far back as the 6th century AD, people have tested the WEP simply by dropping two objects of different masses, and observing no detectable difference. Astronauts even performed the test to low accuracy on the Moon with a feather and hammer, which reached the surface at the same time. The most precise tests to date use a rotating torsion pendulum, which can measure the acceleration of different samples toward the Earth, Sun, or center of the Milky Way. However, this technique is approaching technical limitations.In their proposed experiment, Dr. Reasenberg and Dr. Phillips compare the accelerations of two test mass assemblies dropped inside an experiment chamber that is carried by a NASA Black Brant XII rocket. The experiment is designed to be conducted at altitudes that range from about 800 km to 1200 km, and includes eight drops of 40 seconds each. Both test mass assemblies consist of a pair of aluminum cubes connected by a short rod or pair of rods. In one test mass assembly, holes are drilled into the aluminum, and lead tubes are inserted into the holes. Although lead is denser than aluminum, the objects are designed so that they both have the same mass, and only the material is different. The two objects are laid in a crisscrossed configuration in the same plane, so that the four aluminum cubes form a square. Above this configuration, four tracking frequency laser gauges are aimed down at the four cubes toward Earth’s center of mass, measuring each cube’s acceleration as it falls to Earth.center_img More information: Robert D. Reasenberg and James D. Phillips. “A weak equivalence principle test on a suborbital rocket.” Class. Quantum Grav. 27 (2010) 095005 (14pp). Doi:10.1088/0264-9381/27/9/095005Harvard-Smithsonian Center for Astrophysics: Test of the Weak Equivalence Principle www.cfa.harvard.edu/PAG/index_files/Page1098.htm 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. Samsung Introduces New Bluetooth Headset Designed by Bang and Olufsen Explore furtherlast_img read more

Researchers create computer model that simulates anesthesias impact on brain

first_img More information: Percolation Model of Sensory Transmission and Loss of Consciousness Under General Anesthesia, Phys. Rev. Lett. 115, 108103 – Published 4 September 2015. dx.doi.org/10.1103/PhysRevLett.115.108103ABSTRACTNeurons communicate with each other dynamically; how such communications lead to consciousness remains unclear. Here, we present a theoretical model to understand the dynamic nature of sensory activity and information integration in a hierarchical network, in which edges are stochastically defined by a single parameter p representing the percolation probability of information transmission. We validate the model by comparing the transmitted and original signal distributions, and we show that a basic version of this model can reproduce key spectral features clinically observed in electroencephalographic recordings of transitions from conscious to unconscious brain activities during general anesthesia. As p decreases, a steep divergence of the transmitted signal from the original was observed, along with a loss of signal synchrony and a sharp increase in information entropy in a critical manner; this resembles the precipitous loss of consciousness during anesthesia. The model offers mechanistic insights into the emergence of information integration from a stochastic process, laying the foundation for understanding the origin of cognition. © 2015 Phys.org (Phys.org)—A team of researchers working at the University of Pittsburgh has created a computer model that simulates in some interesting ways, the process that occurs when anesthesia causes the human brain to essentially shut down. In their paper published in Physical Review Letters, the team describes how they built their model, which aspects of consciousness it represents and the ways in which it mimics human anatomy. Explore further Thalamocortical and corticocortical coherence. Credit: Phys. Rev. Lett. 115, 108103 – Published 4 September 2015. DOI: 10.1103/PhysRevLett.115.108103 Citation: Researchers create computer model that simulates anesthesia’s impact on brain (2015, September 8) retrieved 18 August 2019 from https://phys.org/news/2015-09-simulates-anesthesia-impact-brain.htmlcenter_img Despite huge advances in the development of drugs used to anesthetize people during surgery, scientists still do not know how or why it works, which is irksome because if it could be explained than we might make some inroads towards understanding the nature of consciousness itself. In this new effort, the team in Pittsburgh created a computer model framed around nodes that are meant to mimic neurons or whole parts of the brain and the signals that are sent between them. The model is based on an idea that suggests sudden changes in consciousness brought about by the introduction of an anesthetic are caused by a global change in the network responsible for carrying signals through a neural network—a sudden restoration of the network would then correspond to the sudden awakening that occurs with patients coming to after surgery. To mimic such a situation the researchers built a network of nodes with signaling between them similar to the gamma and beta waves that can be recorded during normal human consciousness, the alpha waves that occur during times of relaxation and the delta waves that are the hallmark of deep sleep. To allow for such globalized changes, the researches assigned a variable (p) to each node that represented transmission flow—changing the value changed the ability of an individual node to read, react and transmit information that came to it. But, because it was a global variable, the researchers were able to impact the way information was processed and retransmitted for all of the nodes at the same time. By changing the value of the variable slowly, the researchers were able to find the tipping point, where the network ceased to be able to transmit signals—mimicking a loss of consciousness. But what was truly interesting was that the signaling that occurred naturally mimicked the types of brain waves recorded on an EEG machine as a person becomes unconscious.The researchers are not suggesting that their model actually explains what happens when an anesthetic enters the brain, but are instead offering a possible base on which to begin a way to study what does occur, perhaps leading to a better understanding of how consciousness really does work in the brain. 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. Journal information: Physical Review Letters Researchers reveal brainwave changes in patients receiving nitrous oxidelast_img read more

Enormous dwarf satellite galaxy of Milky Way discovered

first_img Explore further Using data from ESA’s Gaia spacecraft, astronomers have discovered a new Milky Way satellite in the constellation Antlia. The newly found dwarf galaxy, named Antlia 2, is several times larger when compared to other systems of similar luminosity. The finding is detailed in a paper published November 9 on arXiv.org. Citation: Enormous dwarf satellite galaxy of Milky Way discovered (2018, November 27) retrieved 18 August 2019 from https://phys.org/news/2018-11-enormous-dwarf-satellite-galaxy-milky.html © 2018 Science X Network 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. More information: G. Torrealba et al. The hidden giant: discovery of an enormous Galactic dwarf satellite in Gaia DR2, arXiv:1811.04082 [astro-ph.GA].arxiv.org/abs/1811.04082 Gaia spots a ‘ghost’ galaxy next door Distribution of the MW dwarf satellites in Galactocentric coordinates. The position of Ant 2 is shown as a red filled circle. The positions of the Magellanic clouds are shown in blue. Other MW dwarf galaxies are shown in black. Image credit: Torrealba et al., 2018. The Milky Way is known to be orbited by dozens of smaller, gravitationally bound galaxies. Although the list of identified satellites is relatively long, astronomers believe that some are still undetected.With the aim of expanding the list of the Milky Way’s satellites, a team of astronomers led by Gabriel Torrealba of Academia Sinica in Taipei, Taiwan, has conducted a search for new satellites, especially dwarf galaxies. For their study, the researchers used a combination of astrometry, photometry and variability data provided by Gaia Data Release 2 (DR2).The search resulted in the finding of an enormous, faint dwarf galaxy orbiting the Milky Way, which has received the designation Antlia 2 (or Ant 2 for short). Its nature was confirmed by spectroscopic observations with the 2dF+AAOmega Spectrograph on the 3.9 m Anglo-Australian Telescope and archival DECam imaging. The astronomers refer to the newly found satellite as “the hidden giant,” given that the galaxy turned out to be significantly much larger than other systems in the Local Group with similar luminosity.”In this paper, we use Gaia Data Release 2 (GDR2, Gaia Collaboration et al. 2018b) to discover and analyze a new dwarf satellite galaxy orbiting the Milky Way. The discovery was made at the Flatiron Gaia Sprint 2018,” the researchers wrote in the paper.Ant 2 is located some 424,000 light years away from the Earth and is estimated to be about 11.2 billion years old. The galaxy has an angular half-light radius of approximately 9,300 light years and a magnitude of –8.5 mag.The astronomers note that these values make Ant 2 similar in extent to the Large Magellanic Cloud (LMC), but with a luminosity around 4,000 times fainter. They noted that when compared to systems of similar luminosity, Ant 2 is several times larger, while for objects of comparable size, it is about three orders of magnitude fainter.The researchers also report that Ant 2 is the most diffuse object detected to date, about 100 times more diffuse than the so-called ultra diffuse galaxies (UDGs). Moreover, UDGs with sizes similar to Ant 2 are typically about six mag brighter.In concluding remarks, the authors of the paper emphasized the unusual properties of Ant 2, which may prove that dwarf galaxy formation can proceed at surface brightness and density levels significantly lower than those so far observed. “Ant 2 could be the tip of an iceberg—a population of extremely diffuse galactic dwarf galaxies even fainter than the numerous satellites detected in wide-area photometric surveys over the past two decades. Fortunately, Gaia data – as illustrated by this work – may be the key to testing this hypothesis,” the researchers concluded.last_img read more

Aiming to breach the double ton mark now Vijay

first_imgWith a penchant for scoring big Test hundreds, Indian opener Murali Vijay is now aiming to cross the 200-run barrier as he approaches the next phase of his cricketing career.The Tamil Nadu batsman, who scored a patient 150 in the ongoing one-off rain-hit Test against Bangladesh here, has registered six centuries in 32 matches with scores of 139, 167, 153, 146, 144 and 150 adorning the list. The 31-year-old player now wants to take it to the next level. Also Read – Khel Ratna for Deepa and Bajrang, Arjuna for Jadeja“Yes, I am aiming for that. I have been batting well and scoring these 140s and 150s. Now it’s time to take another step and aim for a double hundred. To achieve that I am working on my fitness.“As I said earlier, after having batted long enough to get to 150 your body tires out due to the external factors like the heat and humidity. That affects your mind. If you have the will to do it, you will. I have that will and I am doing everything I can to achieve that. Hopefully it is around the corner,” Vijay told bcci.tv when asked about his love for big scores. Also Read – Endeavour is to facilitate smooth transition: ShastriVijay was instrumental in helping India get to 462 for six declared in the first innings after he stitched a 283-run opening stand with Shikhar Dhawan (173). The Chennai-born player said he being friends with his opening partner has helped him.“It is said that for the openers it is important to be good friends off the field in order to succeed as a pair on it. And it is absolutely true. Shikhar and I share a very good rapport off the field and that helps us in the middle.Although our games are different, we know each other’s games very well.last_img read more

Worldclass autism township set to come up near Kolkata

first_imgKolkata: In a one-of-its-kind initiative, a private firm, in association with the state government, is set to build a world-class autism township near Kolkata, where children and adults suffering from the developmental disorder can receive training, treatment and boarding facilities. The India Autism Center (IAC) — a non-profit organization under Section 8 of Companies Act, 2013 — is expected to come up over a 52-acre plot at Sirakol in South 24 Parganas in the next five years. Also Read – Rain batters Kolkata, cripples normal lifeA joint effort by Ratnabali Group and the state — the estimated cost for building the township has been pegged at Rs 500 crore, a company official said. The soft launch of the project has been scheduled for January, next year, the official said. Suresh Somani, the joint managing director of Ratnabali Investment Pvt Ltd, said the project, announced during the Bengal Global Business Summit (BGBS) earlier this year, will also have provisions for training teachers, who would be dealing with those suffering from the disorder. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedFinance minister Amit Mitra, during the BGBS meet in January, had highly appreciated the initiative and promised all support to it, he said. “It will be the first centre of its kind, not just in India, but globally, with housing facilities for 350 residents and daycare centre for over 200 children, adolescents and adults. The construction work for the township will begin next year,” Somani said. IAC will also have an administrative wing and a guest house, where parents of those receiving training at the institute can put up for a few days, he said. “There will be international tie-ups and the institute will be absolutely different from any of the centres that we have now. The township, which is expected to come up by 2023, will ensure holistic development of those suffering from autism,” he added.last_img read more

CESCs Fountain of Joy enthralls people on New Year

first_imgKolkata: The CESC Fountain of Joy, located at Maidan opposite Victoria Memorial, wore a spectacular look on the first day of 2019. The 150-channel musical fountain, which has been recently refurbished, introduced a special music programme to provide joy to the citizens of Kolkata. As an added attraction on New Year’s eve, the CESC Fountain of Joy became functional from 5 pm. Of special attraction is the selection of Rabindra Sangeet being played at the musical fountain. Also Read – Rain batters Kolkata, cripples normal lifeOne of India’s two three-tier cascading fountains (another being in Vrindaban Garden, Mysore), the Fountain of Joy can operate 25 different patterns with the help of pumps of different capacities. The central nozzle sprays water up to a height of 25 metres, which is as high as an eight-storey building. The CESC Fountain of Joy uses the DMS protocol by integrating a computer with embedded software that allows integration of musical choreography with water features, light and sound.last_img read more

Showcasing emerging artists

first_imgExhibiting an eclectic mix of affordable artworks by some of India’s young and emerging artists, Gallerie Nvya presented the VIII edition of “WITHIN REACH.” The art works are in varied genres and mediums i.e., paintings and sculptures. A special preview was held at the gallery to announce the commencement of the exhibition.Hosted by Tripat Kalra, Founder – Director, Gallerie Nvya and curated by Meher Kalra, Executive Director, Gallerie Nvya, the preview was attended by well known names from Delhi’s art circle. Seen at the occasion were participating artists Sandeep Jigdung, Aditi Saigal, Lal Bahadur Singh, Niraja Bhuwal, Bhuwal Prasad and Sanchit Raj. Also Read – Add new books to your shelf “Within Reach VIII” is an annual enterprise of Gallerie Nvya to put together a collection of original art work; affordable and appealing in nature to suit homes as well as corporate offices. For Nvya this is an opportunity to share and make available art that stands on the threshold of recognition and is filled with promise. Through the show Gallerie Nvya provides a platform for emerging artists in a space shared with more established names; affirm aesthetic sensibility, and celebrate the creative impulse that weaves color and form into variegated manifestations of visual reality. Also Read – Over 2 hours screen time daily will make your kids impulsiveSpeaking at the occasion, Meher Kalra, Executive Director, Gallerie Nvya, said “Within Reach is an endeavour to promote young talent. It is a platform provided by Gallerie Nvya to showcase upcoming talent. We’ve chosen a wide array of artists for this exhibition and some artists are already prominent in their own right and others have the potential to be known for their talent in the future.”last_img read more