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  • richardmitnick 10:54 am on February 15, 2021 Permalink | Reply
    Tags: "EPFL moves boldly into space with its CHESS satellites", , École Polytechnique Fédérale de Lausanne (CH), , Gaining further insight into the chemical composition of the outermost layers of our atmosphere., The EPFL Spacecraft Team has set itself the ambitious goal of launching two satellites by 2023.   

    From École Polytechnique Fédérale de Lausanne (CH): “EPFL moves boldly into space with its CHESS satellites” 


    From École Polytechnique Fédérale de Lausanne (CH)

    05.02.21 [Just now in social media.]
    Sarah Perrin

    1
    The EPFL Spacecraft Team has set itself the ambitious goal of launching two satellites by 2023. With this bold initiative, this student team hopes to gain further insight into the chemical composition of the outermost layers of our atmosphere.

    2
    Chess. Credit: EPFL.

    3
    New technologies will be tested thanks to the CHESS mission. Chess annotated. Credit: EPFL.

    Designing a satellite and launching it into space is no run-of-the-mill project. Rather, it’s one that forever marks the early careers of the students who take part – just ask the EPFL students who designed the SwissCube, a 1U CubeSat (a small standardized unit measuring 10 cm x 10 cm) launched in 2009. Today, a new group of students, the EPFL Spacecraft Team, is taking on a new challenge. With the support of the EPFL Space Center (eSpace), they are developing a constellation of two satellites, called CHESS, that will be launched in two years. The team is currently seeking additional members and sponsors.

    This ambitious project has already signed on six universities, three companies, 15 professors and 53 students.* The two satellites will work in concert; each one will be a 3U CubeSat bearing primary and secondary payloads. They will orbit at different altitudes – one will travel in a circular orbit at the low altitude of around 550 km, and the other will travel in an elliptic orbit at an altitude oscillating between 400 km and 1,000 km. The constellation will be launched in March 2023 and remain in flight for at least two years.

    This project will give the students who participate each year a chance to learn about complicated space technology and gain experience working on a cross-disciplinary team. “It’s a way to learn the real-world skills required in our industry, like team management, coordination, communication and fundraising,” says Emmanuelle David, the deputy director of eSpace. “These are skills you can’t learn only from a book. And they will let the students become operational as soon as they start their first job or when and if they decide to start their own business.”

    4
    One satellite will be placed in a circular orbit at around 550 km, while the other will travel in an elliptic orbit between 400 km and 1,000 km. Credit: EPFL.

    Understanding the exosphere’s chemistry

    In addition to giving students valuable experience, the CHESS mission will have several other objectives. The first is scientific. As the two satellites orbit around the Earth, they will collect detailed information about the exosphere – the outermost layer of the atmosphere, starting at 400 km above the planet’s surface. Since the satellites will follow separate orbits, they will collect complementary spatial and temporal datasets.

    “The last time this layer of the atmosphere was analyzed in detail was nearly 40 years ago,” says Dr. Rico Fausch, a physicist at the University of Bern’s Space Research & Planetary Sciences Department. “So these updated data will be very useful in helping us better understand the exosphere’s chemistry and how it has changed over time, especially in light of global warming. They will also let us check whether the upper layers of the atmosphere are indeed cooling as recent studies have suggested – which would be another direct consequence of the accumulation of greenhouse gases around our planet.”

    The satellites will collect detailed data on the various gases in the exosphere – nitrogen, oxygen, ozone, carbon dioxide, hydrogen, helium, etc. – and their isotopes. The overall goal is to study temperature fluctuations, the processes and mechanisms by which atmospheric gases escape into space, and how many free-floating electrons and ions there are in the exosphere. Molecules are much harder to find at high altitudes than low ones, since individual particles collide and bind together much more slowly.

    Technological advancements

    The CHESS mission also aims to spur technological innovation. The satellites will be equipped with state-of-the-art instruments, such as the new mass spectrometers being developed jointly by the University of Bern [Universität Bern] (CH) and the company Spacetek Technology AG – two pioneers in this field. The spectrometers will be used to identify specific compounds and their chemical structures by taking mass measurements, and will be lighter and more efficient than the ones used back in the 1980s.

    The satellites will also feature next-generation Global Navigation Satellite System (GNSS) receivers that are lighter, less expensive, and more accurate than existing models. These receivers are being developed jointly by ETH Zürich [Eidgenössische Technische Hochschule Zürich)](CH) and u-blox. They will not only record extremely precise data on the satellites’ positions (on the order of ±1 cm), but also measure air density and the number of free-floating electrons. In addition, the CHESS mission will perform in situ tests of a new kind of solar panel designed specifically for spacecraft, based on technology developed at RUAG. And because the two satellites will send radio communications to ground stations, they will help create a Swiss-wide X-band network – a communications network using an ultra-high-frequency radio band.

    Switzerland’s growing space industry

    “I was lucky enough to work with the team that designed, built and launched SwissCube – which is still operational today, some 11 years later,” says Muriel Richard, an aerospace engineer and the co-founder & CTO of ClearSpace. “I’ve been following the CHESS project closely for the past two years, and I see that these students are just as skilled, smart and motivated – and are worth believing in and investing in. They’ll send these satellites into orbit, that’s for sure!”

    CHESS forms part of a broader trend of growing interest in space-industry R&D, both at EPFL and in Switzerland as a whole. The project will help train the next generation of aerospace engineers, pull together skills from a wide range of fields, expand the existing space-industry network and forge ties among the scientific community.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL (CH) is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
  • richardmitnick 11:13 pm on January 20, 2021 Permalink | Reply
    Tags: "m-bits", "Silicon memory?", , École Polytechnique Fédérale de Lausanne (CH), , , , , Metamaterial can be reprogrammed with different properties., Metamaterials=“beyond matter”- engineered materials with properties not found in nature., You can activate and deactivate individual cells by applying a magnetic field.   

    From École Polytechnique Fédérale de Lausanne (CH) via COSMOS (AU): “Silicon memory?” 


    From École Polytechnique Fédérale de Lausanne (CH)

    via

    Cosmos Magazine bloc

    COSMOS (AU)

    21 January 2021
    Deborah Devis

    Metamaterial can be reprogrammed with different properties.

    1
    Credit: Matejmo / Getty Images.

    If you need a material that can literally be changed to suit you over time, look no further.

    Metamaterials – meaning “beyond matter” – are engineered materials with properties not found in nature. This gives them unique scope to work outside of the realms of “normal” acquired materials.

    One such example has recently been reported in Nature by Tian Chen, of École Polytechnique Fédérale de Lausanne, Switzerland, who designed a metamaterial that can be reprogrammed to have different mechanical properties after it is already made.

    “I wondered if there was a way to change the internal geometry of a material’s structure after it’s been created,” says Chen. “The idea was to develop a single material that can display a range of physical properties, like stiffness and strength, so that materials don’t have to be replaced each time.

    “For example, when you twist your ankle, you initially have to wear a stiff splint to hold the ankle in place. Then as it heals, you can switch to a more flexible one. Today you have to replace the entire splint, but the hope is that one day, a single material can serve both functions.”

    The material is made of small mechanical bits, called m-bits, that are reminiscent of computer bits.

    In a hard drive, tiny pieces of digital information can be stored as bits. Magnetic bits can be programmed to switch between the values of 0 and 1, or on/off, by magnetising them in different directions to confer binary information. That binary code can be controlled by an external electromagnetic circuit, which changes the direction of those bits to recode the hard driver with a new memory.

    So, if you’re storing your favourite song on a hard drive, the direction of those bits change based on the code that is imparted, and the digital properties of the hard-drive are altered to include the memory of how to play your song.

    This principal is somewhat like Chen’s material, except that he used mechanical units instead. His m-bits are made of silicon and magnetic powder and have a unique shape that allows each individual cell to move between a compressed and decompressed state. These two states act as the programmable binary code, like computer bits.

    2
    Slow-motion captures of programming by switching the equilibrium of the bistable shell. Credit: Tian Chen.

    This essentially means that the material can contain a memory about what it is supposed to be.

    “You can activate and deactivate individual cells by applying a magnetic field. That modifies the internal state of the metamaterial, and consequently its mechanical properties,” says Chen.

    The property that can be altered in this way is the stiffness of the material. When the cells are switched on by the magnetic field, the material is stiff; when they’re switched off, the material is more flexible.

    If that isn’t incredible enough, its possible to program various combinations of the on/off cells to provide a range of flexibility, basically whenever it’s needed.

    This is the first report that shows both programmed memory and physical change imparted by bits in a single material.

    This extraordinary combination of computer science and mechanical engineering strives to find the sweet spot between static material and machine. This unlocks potential materials that might be used in a plethora of useful items, from prosthetics to aeronautics to shock absorption in orthopaedic shoes.

    A few things need to be sorted out before it reaches the usable stage, though.

    “We could design a method for creating 3D structures, since what we’ve done so far is only in 2D,” says Pedro Reis, the leader of Chen’s lab at École Polytechnique Fédérale de Lausanne . “Or we could shrink the scale to make even smaller metamaterials.”

    Regardless, the ability to program the memory of materials so they’ll change properties is a very exciting development indeed.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL (CH) is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
  • richardmitnick 11:52 am on December 22, 2020 Permalink | Reply
    Tags: "Crossing the artificial intelligence thin red line?", , École Polytechnique Fédérale de Lausanne (CH), , Stuart Russell: There is huge upside potential in AI but we are already seeing the risks from the poor design of AI systems including the impacts of online misinformation; impersonation; and deception   

    From École Polytechnique Fédérale de Lausanne (CH): “Crossing the artificial intelligence thin red line?” 


    From École Polytechnique Fédérale de Lausanne (CH)

    22.12.20
    Tanya Petersen

    1

    EPFL computer science professor tells conference that AI has no legitimate roll in defining, implementing, or enforcing public policy.

    Artificial intelligence shapes our modern lives. It will be one of the defining technologies of the future, with its influence and application expected to accelerate as we go through the 2020s. Yet, the stakes are high; with the countless benefits that AI brings, there is also growing academic and public concern around a lack of transparency, and its misuse, in many areas of life.

    It’s in this environment that the European Commission has become one of the first political institutions in the world to release a white paper that could be a game-changer towards a regulatory framework for AI. In addition, this year the European Parliament adopted proposals on how the EU can best regulate artificial intelligence to boost innovation, ethical standards and trust in technology.

    Recently, an all-virtual conference on the ‘Governance Of and By Digital Technology’ hosted by EPFL’s International Risk Governance Center (IRGC) and the European Union’s Horizon 2020 TRIGGER Project explored the principles needed to govern existing and emerging digital technologies, as well as the potential danger of decision-making algorithms and how to prevent these from causing harm.

    Stuart Russell, Professor of Computer Science at the University of California, Berkeley and author of the popular textbook, Artificial Intelligence: A Modern Approach, proposed that there is huge upside potential in AI, but we are already seeing the risks from the poor design of AI systems, including the impacts of online misinformation, impersonation and deception.

    “I believe that if we don’t move quickly, human beings will just be losing their rights, their powers, their individuality and becoming more and more the subject of digital technology rather than the owners of it. For example, there is already AI from 50 different corporate representatives sitting in your pocket stealing your information, and your money, as fast as it can, and there’s nobody in your phone who actually works for you. Could we rearrange that so that the software in your phone actually works for you and negotiates with these other entities to keep all of your data private?” he asked.

    Reinforcement learning algorithms, that select the content people see on their phones or other devices, are a major problem he continued, “they currently have more power than Hitler or Stalin ever had in their wildest dreams over what billions of people see and read for most of their waking lives. We might argue that running these kinds of experiments without informed consent is a bad idea and, just as we have with pharmaceutical products, we need to have stage 1, 2, and 3 trials on human subjects and look at what effect these algorithms have on people’s minds and behavior.”

    Beyond regulating artificial intelligence aimed at individual use, one of the conference debates focused on how governments might use AI in developing and implementing public policy in areas such as healthcare, urban development or education. Bryan Ford, an Associate Professor at EPFL and head of the Decentralized and Distributed Systems Laboratory (DEDIS) in the School of Communication and Computer Sciences, argued that while the cautious use of powerful AI technologies can play many useful roles in low-level mechanisms used in many application domains, it has no legitimate role to play in defining, implementing, or enforcing public policy.

    “Matters of policy in governing humans must remain a domain reserved strictly for humans. For example, AI may have many justifiable uses in electric sensors to detect the presence of a car – how fast it is going or whether it stopped at an intersection, but I would claim AI does not belong anywhere near the policy decision of whether a car’s driver warrants suspicion and should be stopped by Highway Patrol.”

    “Because machine learning algorithms learn from data sets that represent historical experience, AI driven policy is fundamentally constrained by the assumption that our past represents the right, best, or only viable basis on which to make decisions about the future. Yet we know that all past and present societies are highly imperfect so to have any hope of genuinely improving our societies, governance must be visionary and forward looking,” Professor Ford continued.

    Artificial intelligence is heterogeneous and complex. When we talk about the governance of, and by, AI are we talking about machine learning, neural networks or autonomous agents, or the different applications of any of these in different areas? Likely, all the above in many different applications. We are only at the beginning of the journey when it comes to regulating artificial intelligence, one that most participants agreed has geopolitical implications.

    “These issues may lead directly to a set of trade and geostrategic conflicts that will make them all the more difficult to resolve and all the more crucial. The question is not only to avoid them but to avoid the decoupling of the US from Europe, and Europe and the US from China, and that is going to be a significant challenge economically and geo-strategically,” suggested John Zysman, Professor of Political Science at the University of California, Berkeley and co-Director of the Berkeley Roundtable on the International Economy.

    “Ultimately, there is a thin red line that AI should not cross and some regulation, that balances the benefits and risks from AI applications, is needed. The IRGC is looking at some of the most challenging problems facing society today, and it’s great to have them as part of IC,” said James Larus, Dean of the IC School and IRGC Academic Director.

    Concluding the conference, Marie-Valentine Florin, Executive Director of the IRGC reminded participants that artificial intelligence is a means to an end, not the end, “as societies we need a goal. Maybe that could be something like the Green Deal around sustainability to perhaps give a sense to today’s digital transformation. Digital transformation is the tool, and I don’t think society has collectively decided a real objectivel for it yet. That’s what we need to figure out.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL (CH) is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
  • richardmitnick 12:39 pm on December 21, 2020 Permalink | Reply
    Tags: "When light and atoms share a common vibe", , École Polytechnique Fédérale de Lausanne (CH), In the new study EPFL researchers managed to entangle the photon and the phonon (i.e. light and vibration) produced in the fission of an incoming laser photon inside the crystal., , , , ,   

    From École Polytechnique Fédérale de Lausanne (CH): “When light and atoms share a common vibe” 


    From École Polytechnique Fédérale de Lausanne (CH)

    Scientists from EPFL, MIT, and CEA Saclay demonstrate a state of vibration that exists simultaneously at two different times. They evidence this quantum superposition by measuring the strongest class of quantum correlations between light beams that interact with the vibration.


    When light and atoms share a common vibe.

    An especially counter-intuitive feature of quantum mechanics is that a single event can exist in a state of superposition – happening bothhereandthere, or bothtodayandtomorrow.

    Such superpositions are hard to create, as they are destroyed if any kind of information about the place and time of the event leaks into the surrounding – and even if nobody actually records this information. But when superpositions do occur, they lead to observations that are very different from that of classical physics, questioning down to our very understanding of space and time.

    Scientists from EPFL, MIT, and CEA Saclay, publishing in Science Advances, demonstrate a state of vibration that exists simultaneously at two different times, and evidence this quantum superposition by measuring the strongest class of quantum correlations between light beams that interact with the vibration.

    The researchers used a very short laser-pulse to trigger a specific pattern of vibration inside a diamond crystal. Each pair of neighboring atoms oscillated like two masses linked by a spring, and this oscillation was synchronous across the entire illuminated region. To conserve energy during this process, a light of a new color is emitted, shifted toward the red of the spectrum.

    This classical picture, however, is inconsistent with the experiments. Instead, both light and vibration should be described as particles, or quanta: light energy is quantized into discrete photons while vibrational energy is quantized into discrete phonons (named after the ancient Greek “photo = light” and “phono = sound”).

    The process described above should therefore be seen as the fission of an incoming photon from the laser into a pair of photon and phonon – akin to nuclear fission of an atom into two smaller pieces.

    But it is not the only shortcoming of classical physics. In quantum mechanics, particles can exist in a superposition state, like the famous Schrödinger cat being alive and dead at the same time.

    Even more counterintuitive: two particles can become entangled, losing their individuality. The only information that can be collected about them concerns their common correlations. Because both particles are described by a common state (the wavefunction), these correlations are stronger than what is possible in classical physics. It can be demonstrated by performing appropriate measurements on the two particles. If the results violate a classical limit, one can be sure they were entangled.

    In the new study, EPFL researchers managed to entangle the photon and the phonon (i.e., light and vibration) produced in the fission of an incoming laser photon inside the crystal. To do so, the scientists designed an experiment in which the photon-phonon pair could be created at two different instants. Classically, it would result in a situation where the pair is created at time t1 with 50% probability, or at a later time t2 with 50% probability.

    But here comes the “trick” played by the researchers to generate an entangled state. By a precise arrangement of the experiment, they ensured that not even the faintest trace of the light-vibration pair creation time (t1 vs. t2) was left in the universe. In other words, they erased information about t1 and t2. Quantum mechanics then predicts that the phonon-photon pair becomes entangled, and exists in a superposition of time t1andt2. This prediction was beautifully confirmed by the measurements, which yielded results incompatible with the classical probabilistic theory.

    By showing entanglement between light and vibration in a crystal that one could hold in their finger during the experiment, the new study creates a bridge between our daily experience and the fascinating realm of quantum mechanics.

    “Quantum technologies are heralded as the next technological revolution in computing, communication, sensing, says Christophe Galland, head of the Laboratory for Quantum and Nano-Optics at EPFL and one of the study’s main authors. “They are currently being developed by top universities and large companies worldwide, but the challenge is daunting. Such technologies rely on very fragile quantum effects surviving only at extremely cold temperatures or under high vacuum. Our study demonstrates that even a common material at ambient conditions can sustain the delicate quantum properties required for quantum technologies. There is a price to pay, though: the quantum correlations sustained by atomic vibrations in the crystal are lost after only 4 picoseconds — i.e., 0.000000000004 of a second! This short time scale is, however, also an opportunity for developing ultrafast quantum technologies. But much research lies ahead to transform our experiment into a useful device — a job for future quantum engineers.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL (CH) is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
  • richardmitnick 6:27 pm on December 9, 2020 Permalink | Reply
    Tags: "'Game changer' perovskite can detect gamma rays", , , École Polytechnique Fédérale de Lausanne (CH), , , , ,   

    From École Polytechnique Fédérale de Lausanne (CH): “‘Game changer’ perovskite can detect gamma rays” 


    From École Polytechnique Fédérale de Lausanne (CH)

    09.12.20
    Nik Papageorgiou

    1
    Scientists at EPFL have developed a game-changing perovskite material that can be used as a cheaper and highly efficient alternative to gamma-ray detectors.

    Perovskites are materials made up of organic compounds bound to a metal. Propelled into the forefront of materials’ research because of their structure and properties, perovskites are earmarked for a wide range of applications, including in solar cells, LED lights, lasers, and photodetectors.

    That last application, photo – or light – detection, is of particular interest to scientists at EPFL’s School of Basic Sciences who have developed a perovskite that can detect gamma rays. Led by the labs of Professors László Forró and Andreas Pautz, the researchers have published their work in Advanced Science.

    “This photovoltaic perovskite crystal, grown in this kilogram size, is a game changer,” says Forró. “You can slice it into wafers, like silicon, for optoelectronic applications, and, in this paper, we demonstrate its utility in gamma-ray detection.”

    Monitoring gamma rays

    Gamma-rays are a kind of penetrating electromagnetic radiation that is produced from the radioactive decay of atomic nuclei, e.g., in nuclear or even supernovae explosions. Gamma-rays are on the shortest end of the electromagnetic spectrum, which means that they have the highest frequency and the highest energy. Because of this, they can penetrate almost any material, and are used widely in homeland security, astronomy, industry, nuclear power plants, environmental monitoring, research, and even medicine, for detecting and monitoringtumors and osteoporosis.

    But exactly because gamma rays can affect biological tissue, we have to be able to keep an eye on them. To do this, we need simple, reliable, and cheap gamma-ray detectors. The perovskite that the EPFL scientists developed is based on crystals of methylammonium lead tribromide (MAPbBr3) and seems to be an ideal candidate, meeting all these requirements.

    Crystal-clear advantages

    Perovskites are first “grown” as crystals, and the quality and clarity of the crystals determines the efficiency of the material when it is turned into thin films that can be used in devices like solar panels.

    The perovskite crystals that the EPFL scientists made show high clarity with very low impurities. When they tested gamma-rays on the crystals, they found that they generated photo-carriers with a high “mobility-lifetime product”, which is a measurement of the quality of radiation detectors. In short, the perovskite can efficiently detect gamma rays at room temperatures, simply by resistivity measurement.

    Cheaper and scalable synthesis

    The MAPbBr3 part of the “metal halide” family of perovskites, meaning that, unlike market-leading crystals, its crystals can be grown from abundant and low-cost raw materials. The synthesis takes place in solutions close to room temperature without needing expensive equipment.

    Of course, this is not the first perovskite made for gamma ray-detection. But the volume of most lab-grown metal halide perovskites used for this is limited to about 1.2 ml, which is hardly scalable to commercial levels. However, the team at EPFL also developed a unique method called ‘oriented crystal-crystal intergrowth’ that allowed them to make a whole liter of crystals weighing 3.8 kg in total.

    “Personally, I enjoyed very much to work at the common frontiers of condensed matter physics, chemistry and reactor physics, and to see that this collaboration could lead to important application to our society,” says Pavao Andričević, the lead-author.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL (CH) is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
  • richardmitnick 10:44 am on October 29, 2020 Permalink | Reply
    Tags: "Deep Learning Algorithms Helping to Clear Space Junk from our Skies", École Polytechnique Fédérale de Lausanne (CH)   

    From École Polytechnique Fédérale de Lausanne (CH): “Deep Learning Algorithms Helping to Clear Space Junk from our Skies” 


    From École Polytechnique Fédérale de Lausanne (CH)

    29.10.20
    Tanya Petersen

    1
    The European Union has allocated €86 million to a project designed to capture and remove a piece of space debris weighing 120kg, which has been in orbit around the Earth since 2013. The startup ClearSpace, working from the EPFL Innovation Park, will seek private funds to raise the total to €100 million.

    EPFL researchers are at the forefront of developing some of the cutting-edge technology for the European Space Agency’s first mission to remove space debris from orbit.

    How do you measure the pose – that is the 3D rotation and 3D translation – of a piece of space junk so that a grasping satellite can capture it in real time in order to successfully remove it from Earth’s orbit? What role will deep learning algorithms play? And, what is real time in space? These are some of the questions being tackled in a ground-breaking project, led by EPFL spin-off, ClearSpace, to develop technologies to capture and deorbit space debris.

    With more than 34,000 pieces of junk orbiting around the Earth, their removal is becoming a matter of safety. Earlier this month an old Soviet Parus navigation satellite and a Chinese ChangZheng-4c rocket were involved in a near miss and in September the International Space Station conducted a maneuver to avoid a possible collision with an unknown piece of space debris, whilst the crew of the ISS Expedition 63 moved closer to their Soyuz MS-16 spacecraft to prepare for a potential evacuation. With more junk accumulating all the time, satellite collisions could become commonplace, making access to space dangerous.

    ClearSpace-1, the company’s first mission set for 2025, will involve recovering the now obsolete Vespa Upper Part, a payload adapter orbiting 660 kilometers above the Earth that was once part of the European Space Agency’s Vega rocket, to ensure that it re-enters the atmosphere and burns up in a controlled way.

    One of the first challenges is to enable the robotic arms of a capture rocket to approach the Vespa from the correct angle. To this end, it will use an attached camera – its ‘eyes’ – to figure out where the space junk is so it can grasp the Vespa and then pull it back into the atmosphere. “A central focus is to develop deep learning algorithms to reliably estimate the 6D pose (3 rotations and 3 translations) of the target from video-sequences even though images taken in space are difficult. They can be over- or under-exposed with many mirror-like surfaces,” says Mathieu Salzmann, a scientist spearheading the project within EPFL’s Computer Vision Laboratory led by Professor Pascal Fua, in the School of Computer and Communication Sciences.

    However, there’s a catch. Nobody has really seen the Vespa for seven years as it’s been spinning in a vacuum in space. We know it’s about 2 meters in diameter, with carbon fibers that are dark and a little shiny, but is this still what it looks like?

    EPFL’s Realistic Graphics Labis simulating what this piece of space junk looks like as the ‘training material’ to help Salzmann’s deep learning algorithms improve over time. “We are producing a database of synthetic images of the target object, including both the Earth backdrop reconstructed from hyperspectral satellite imagery, and a detailed 3D model of the Vespa upper stage. These synthetic images are based on measurements of real-world material samples of aluminium and carbon fiber panels, acquired using our lab’s goniophotometer. This is a large robotic device that spins around a test swatch to simultaneously illuminate and observe it from many different directions, providing us with a wealth of information about the material’s appearance,” says Assistant Professor Wenzel Jakob, head of the lab. Once the mission kicks off, researchers will be able to capture some real-life pictures from beyond our atmosphere and fine tune the algorithms to make sure that they work in situ.

    A third challenge will be the need to work in space, in real-time and with limited computing power onboard the ClearSpace capture satellite. Dr. Miguel Peón, a Senior Post-Doctoral Collaborator with EPFL’s Embedded Systems Lab is leading the work of transferring the deep learning algorithms to a dedicated hardware platform. “Since motion in space is well behaved, the pose estimation algorithms can fill the gaps between recognitions spaced one second apart, alleviating the computational pressure. However, to ensure that they can autonomously cope with all the uncertainties in the mission, the algorithms are so complex that their implementation requires squeezing out all the performance from the platform resources,” says Professor David Atienza, head of ESL.

    t’s clear that designing algorithms to be 100% reliable in such harsh, and relatively unknown, conditions, and that perform in real-time using limited computational resources, is a tremendous challenge. For Salzmann, this is part of the attraction of the project, “we need to be absolutely reliable and robust. From a research perspective, you are typically happy with 90% success but this is something that we cannot really afford in a real mission. But maybe the more exciting aspect of the project is that we are developing an algorithm that will eventually work in space. I find this absolutely amazing and that is what motivates me every day!”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL (CH) is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
  • richardmitnick 8:10 am on October 27, 2020 Permalink | Reply
    Tags: "New system uses floor vibrations to detect building occupants", ...That lets us calculate the number of people in the building as well as where they are located and their trajectory.”, “By installing sensors in a building’s floor slabs we can measure the vibrations created by footsteps..., École Polytechnique Fédérale de Lausanne (CH), Managing buildings’ energy use more efficiently, Safety in retirement homes, The challenge is screening out the background noise caused by spurious events such as a door closing or an object falling to the ground.   

    From École Polytechnique Fédérale de Lausanne (CH): “New system uses floor vibrations to detect building occupants” 


    From École Polytechnique Fédérale de Lausanne (CH)

    27.10.20
    Nathalie Jollien

    1
    © 2020 EPFL Alain Herzog.

    Thanks to a new system developed at EPFL, building owners can detect the number of occupants and track their movement using sensors installed on floor slabs. This novel approach could be particularly useful for enhancing safety in retirement homes or managing buildings’ energy use more efficiently.

    Many buildings, manufacturing sites, shopping malls and other public spaces are equipped with occupant detection systems. These systems generally rely on cameras or occupants’ mobile phones. Such technologies infringe on privacy and may not function in emergencies such as fires. Scientists at ENAC’s Applied Computing and Mechanics Laboratory (IMAC), headed by Professor Ian Smith, have developed an alternative approach. “By installing sensors in a building’s floor slabs, we can measure the vibrations created by footsteps. That lets us calculate the number of people in the building as well as where they are located and their trajectory,” says Slah Drira, the IMAC PhD student who completed his thesis on this topic.

    To each his own gait

    The challenge with Drira’s approach is screening out the background noise caused by spurious events such as a door closing or an object falling to the ground. These events can trigger vibrations similar to those induced by footsteps. Another challenge relates to the vast differences in walking styles – not just between two different people but also by the same person under different circumstances. “The signals our sensors record can vary considerably depending on the person’s anatomy, walking speed, shoe type, health and mood,” says Drira.

    2
    Ian Smith and Slah Drira. © 2020 EPFL Alain Herzog.

    His method uses advanced algorithms – or more specifically, support vector machines – to classify the signals recorded by the sensors. Some interpretation strategies were inspired by the convolutional neural networks often employed in pixel-based image recognition, and can identify the footstep characteristics of specific occupants.

    Real-world testing

    The research team carried out four full-scale floor slabs: one in a seminar room at IMAC, one in an office environment at IMAC, one in the entrance of the MED building at EPFL campus and one in an open-hall space in Singapore. “These four case studies allowed us to validate our occupant detection, localization and tracking system on a larger scale. Unlike existing methods, ours needs fewer sensors – just one for every 15–75 m2, as opposed to one for every 2 m2 – and doesn’t require that the floor slabs have uniform rigidity. What’s more, the localization feature of other methods had been tested only on single individuals,” says Drira.

    The new system has applications in a host of fields. It could be used to enhance energy management protocols in offices, improve building security (like at banks and data centers), find occupants during an emergency and locate patients inside hospitals and retirement homes. This system can do all that without infringing on occupants’ privacy.

    3
    Slah Drira. © 2020 EPFL Alain Herzog.

    Drira’s research was carried out within the scope of the Future Cities Laboratory (FCL) program headed by Professor Ian Smith at the Singapore-ETH Centre – an R&D platform established jointly by ETH Zurich and Singapore’s National Research Foundation (NRF) as part of the NRF’s Campus for Research Excellence And Technological Enterprise (CREATE) initiative. The Centre aims to provide practical solutions to some of the most pressing challenges in urban sustainability, resilience and health.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL (CH) is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
  • richardmitnick 11:50 am on October 14, 2020 Permalink | Reply
    Tags: "EPFL scientist gains fresh insight into the origins of earthquakes", École Polytechnique Fédérale de Lausanne (CH), , , , , ,   

    From École Polytechnique Fédérale de Lausanne (CH): “EPFL scientist gains fresh insight into the origins of earthquakes” 


    From École Polytechnique Fédérale de Lausanne (CH)

    14.10.20
    Rémi Carlier

    1
    The speed and intensity with which seismic waves propagate after an earthquake depend mainly on forces occurring deep inside the rocks along a fault line, according to a study by EPFL scientist François Passelègue. His sophisticated models are giving us fresh insight into the factors that can trigger an earthquake.

    Sometimes barely noticeable, and at other times devasting, earthquakes are a major geological phenomenon which provide a stark reminder that our planet is constantly evolving. Scientists have made significant progress in understanding these events over the past 50 years thanks to sensors set up around the world. And while we now know that earthquakes are caused by shifts in tectonic plates, a lot remains to be learned about how and why they occur.

    Passelègue, a scientist at ENAC’s Laboratory of Experimental Rock Mechanics (LEMR), has been studying the dynamics of faults – or the areas between tectonic plates, where most earthquakes occur – for the past ten years. He recently made a major breakthrough in understanding the rupture mechanisms that eventually lead to seismic shifts along fault lines. His findings were published in the prestigious Nature Communications on 12 October 2020.

    ______________________________________________
    “We know that rupture speeds can vary from a few millimeters per second to a few kilometers per second once nucleation occurs [the process by which a slip expands exponentially]. But we don’t know why some ruptures propagate very slowly and others move quickly. However, that’s important to know because the faster the propagation, the quicker the energy that accumulates along the fault is released.”
    François Passelègue
    ______________________________________________

    An earthquake will generally release the same amount of energy whether it moves slowly or quickly. The difference is that if it moves slowly, its seismic waves can be absorbed by the surrounding earth. These types of slow earthquakes are just as frequent as regular ones; it’s just that we can’t feel them. In extremely fast earthquakes – which occur much less often – the energy is released in just a few seconds through potentially devasting high-frequency waves. That’s what sometimes occurs in Italy, for example. The country is located in a friction zone between two tectonic plates. While most of its earthquakes aren’t (or are barely) noticeable, some of them can be deadly – like the one on 2 August 2016 that left 298 people dead.


    Powerful earthquake strikes Central Italy | New York Times

    In his study, Passelègue developed an experimental fault with the same temperature and pressure conditions as an actual fault running 8 km deep. He installed sensors along the fault to identify the factors causing slow vs. fast rupture propagation. “There are lots of hypotheses out there – most scientists think it’s related to the kind of rock. They believe that limestone and clay tend to result in slow propagation, whereas harder rocks like granite are conducive to fast propagation,” he says. Passelègue’s model uses a complex rock similar to granite. He was able to replicate various types of slip on his test device, and found that “the difference isn’t necessarily due to the properties of the surrounding rock. A single fault can demonstrate all kinds of seismic mechanisms.”

    2
    In his study, Passelègue developed an experimental fault with the same temperature and pressure conditions as an actual fault running 8 km deep. © 2020 Alain Herzog.

    Passelègue’s experiments showed that the amount of energy released during a slip, and the length of time over which it’s released, depend on the initial strain exerted along the fault; that is, the force applied on the fault line, generally from shifting tectonic plates. By applying forces of different magnitudes to his model, he found that higher strains triggered faster ruptures and lower strains triggered slower ruptures. “We believe that what we observed in the lab would apply under real-world conditions too,” he says.

    Earthquakes may not be random occurrences

    Using the results of his model, Passelègue developed equations that factor in the initial strain on a fault and not just the amount of energy accumulated immediately before a slip, which was the approach used in other equations until now.

    Passelègue warns that his model cannot be used to determine when or where an earthquake will occur. Since faults run too deep, scientists still aren’t able to continually measure the strain on rock right along a fault. “We can identify how much strain there needs to be to cause a rupture, but since we don’t know how much a fault is ‘loaded up’ with energy deep underground, we can’t predict the rupture speed.”

    3
    In his study, Passelègue developed an experimental fault with the same temperature and pressure conditions as an actual fault running 8 km deep. © 2020 Alain Herzog.

    One implication of Passelègue’s research is that earthquakes may not be as random as we thought. “Most people think that faults that have been stable for a long time will never cause a serious earthquake. But we found that any kind of fault can trigger many different types of seismic events. That means a seemingly benign fault could suddenly rupture, resulting in a fast and dangerous wave propagation.”

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network projectEarthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL (CH) is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
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