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Hier — 6 août 2020Vos flux RSS

How To Use Wi-Fi Networks To Ensure a Safe Return to Campus

Par Jan Dethlefs
IEEE COVID-19 coverage logo, link to landing page

This is a guest post. The views expressed here are solely those of the authors and do not represent positions of IEEE Spectrum or the IEEE.

Universities, together with other operators of large spaces like shopping malls or airports, are currently facing a dilemma: how to return to business as fast as possible, while at the same time providing a safe environment?

Given that the behavior of individuals is the driving factor for viral spread, key to answering this question will be understanding and monitoring the dynamics of how people move and interact while on campus, whether indoors or outdoors.

Fortunately, universities already have the perfect tool in place:  the campus-wide Wi-Fi network. These networks typically cover every indoor and most outdoor spaces on campus, and users are already registered. All that needs to be added is data analytics to monitor on-campus safety.

We, a team of researchers from the University of Melbourne and the startup Nexulogy, have developed the necessary algorithms that, when fed data already gathered by campus Wi-Fi networks, can help keep universities safe. We have already tested these algorithms successfully at several campuses and other large yet contained environments.

Analysis of Wi-Fi data over the course of a week allows university managers to identify times and places where occupancy levels could be problematic during the pandemic.  
Image: Jan Dethlefs/Nexulogy
Analysis of Wi-Fi data over the course of a week allows university managers to identify times and places where occupancy levels could be problematic during the pandemic.

To date, little attention has been paid to using Wi-Fi networks to track social distancing. Countries like Australia have rolled out smartphone apps to support contact tracing, typically using Bluetooth to determine proximity. A recent Google/Apple collaboration, also using Bluetooth, led to a decentralized protocol for contact monitoring.

Yet the success of these apps mainly relies on people voluntarily downloading them. A study by the University of Oxford estimated that more than 70 percent of smartphone users in the United Kingdom would have to install the app for it to be effective. But adoption is not happening at anything near that scale; the Australian COVIDSafe app, for example, released in April 2020, has only been downloaded by 6 million people by mid-June 2020, or about 24 percent of the population.

Furthermore, this kind of Bluetooth-based tracking does not relate the contacts to a physical location, such as a classroom. This makes it hard to satisfy the requirements of running a safe campus. And data collected by the Bluetooth tracking apps is generally not readily available to the campus owners, so it doesn’t help make their own spaces safer.

Our Wi-Fi based algorithms provide the least privacy-intrusive monitoring mechanisms thus far, because they use only anonymous device addresses; no individual user names are necessary to understand crowd densities and proximity. In the case of a student or campus staff member reporting a positive coronavirus test, the device addresses determined to belong to someone at risk can be passed on authorities with the appropriate privacy clearance. Only then would names be matched to devices, with people at risk informed individually and privately.

Wi-Fi presents the best solution for universities for a couple of reasons: wireless coverage is already campus wide; it is a safe assumption that everyone on campus is carrying at least one Wi-Fi capable device; and virtually everyone living and working on campus registers their devices to have internet access. Such tracking is possible without onerous user-facing app downloads.

Often university executives already have the rights to use the information collected in the wireless system included as part of its Terms and Conditions. In the midst of this pandemic, they now also have a legal or, at least a moral obligation, to use such data to their best ability to improve safety and well-being of everyone on campus.

Using Wi-Fi data, algorithms calculate the population density for specific spaces on campus at particular times. 
Image: Jan Dethlefs/Nexulogy
Using Wi-Fi data, algorithms calculate the population density for specific spaces on campus at particular times.

The process starts by collecting the time and symbolic location (also known as network access point) of Wi-Fi capable devices when they are first detected by the Wi-Fi infrastructure, for example, when a student enters the campus’ Wi-Fi  environment, and then during regular intervals or when they change locations. Then, after consolidating any multiple devices of a single user, our algorithms calculate the number of occupants in a given area. That provides a quick insight into crowd density in any building or outdoor plaza.

Our algorithms can also reconstruct the journey of any user within the Wi-Fi infrastructure, and from that can derive exposure time to other users, spaces visited and transmission risk.

This information lets campus managers do several things. For one, our algorithms can easily identify high risk areas by time and location and flag areas where social distance limits are regularly exceeded. This helps campus managers focus resources on areas that may need more hand sanitizers or more frequent deep cleaning.

For another, imagine an infected staff member has been identified by public health authorities. Based on the health authorities’ request, the university can identify possible infection pathways by tracking the individual’s journeys through the campus. It is possible to backtrack the movement history since the start of the data collection, for days or even weeks if necessary. 

To illustrate the methodology, we assumed one of us had a COVID infection and we reconstructed his journey and exposure to other university visitors during a recent visit to a busy university campus. In the heat map below, you can see that only the conference building showed a significant number of contacts (red bar) with an exposure time of, in this example, more than 30 minutes. While we only detected other individuals by Wi-Fi devices, the university executives could now notify people that potentially have been exposed to an infectious user.

Wi-Fi network data was used to create this heat map of a day spent on a university campus by someone with a hypothetical Covid-19 infection. Other people who were in the same place as the infected person for a significant amount of time (the red bar) could be identified and contacted by university officials. 
Image: Jan Dethlefs/Nexulogy
To illustrate the capabilities of our approach the journey of one of the authors was tracked during the attendance of a conference. The author arrived at 10am passing multiple people. The conference building was busy at the time, but the author was exposed to only around 30 people for a longer period (red bar). After the conference the author picked up coffee on the way out and encountered a small number of people while queueing (yellow). While waiting for a taxi a small number of people walked past, all with exposure time of less than 10 minutes.

This system isn’t without technical challenges. The biggest problem is noise in the system that needs to be removed before the data is useful.

For example, depending on the building layout and wireless network configurations, wireless counts inside specific zones can include passing outside traffic or static devices (like desktop computers). We have developed algorithms to eliminate both without requiring access to any user information.

Even though the identification and management of infection risks is limited to the area covered by the wireless infrastructure, the timely identification of a COVID event naturally benefits areas beyond the campus. Campuses, and even residential campuses in lockdown, have a daily influx of external visitors —staff, contractors, and family members. Those individuals could be identified via telecommunication providers if requested by health authorities.

In the case of someone on campus testing positive for the virus, people they came in contact with, their contact times and places they went to can be identified within minutes. This allows the initiation of necessary measures (e.g. COVID testing or decontamination) in a targeted, timely and cost-effective way.

Since the analytics can happen in the cloud, the software can easily be updated to reflect on new or refined medical knowledge or health regulations, say a new exposure time threshold or physical distancing guidelines.

Privacy is paramount in this process. Understanding population densities and crowd management is done anonymously. Only in the case of someone on campus reporting a confirmed case of the coronavirus  do authorities with the necessary privacy clearance need to connect the devices and the individuals.  Our algorithm operates separately from the identification and notification process.

As universities around the world are eager to welcome students back to the campus, proactive plans need to be in place to ensure the safety and wellbeing of everyone. Wi-Fi is available and ready to help.

Jan Dethlefs is a data scientist and Simon Wei is a data engineer, both at Nexulogy in Melbourne, Australia.  Stephan Winter is a professor and Martin Tomko is a senior lecturer, both in the Department of Infrastructure Engineering at the University of Melbourne, where they work with geospatial data analytics.

IEEE Standards Association Marking World Standards Day With a Video Contest

Par IEEE Standards Association
Image of a woman thinking.
Image: iStockphoto

THE INSTITUTE Every year on 14 October the IEEE Standards Association (IEEE SA) joins the international community in celebrating the importance of standards development and honoring the collaboration of individuals and organizations across the globe that drive technological innovation.

This year’s World Standards Day theme is “Raising the World’s Standards for the Protection of the Planet.” During the past century, large-scale industrial activities, rapid population growth, urbanization, and inequality have negatively impacted the Earth, our lives, and the well-being of future generations. The concept of sustainable development has become more important. Global standards play a key role in supporting the environmental, social, and economic sustainability of our planet and human society.

IEEE SA has several standards and projects—as well as communities and resources—working on sustainable development.

IEEE SA is conducting a video contest, seeking entries that answer the question: How do standards protect the planet? All formats will be considered, including self-recorded and animated works, documentaries, and music videos.

Each video must be online and include a reference to an IEEE standard and its relevance to the theme. It must be original content, run between 15 and 60 seconds in length, be in English or include English subtitles, and include the URL where the video may be found.

Other eligibility requirements and contest rules can be found here.

Up to three videos will be selected, and each winner will receive a US $500 prize. The deadline is 15 September 2020.

Submit your video today.

Recycling Electronic Waste to Make Hybrid Materials

Par Charles Q. Choi

Electronic waste could get recycled into strong, protective coatings for steel, a new study finds.

Recycling typically converts large quantities of items made of a single material, such as aluminum cans or glass bottles, into more of the same. However, this approach is not feasible for complex garbage such as electronic waste, or e-waste, because it contains many different materials that cannot be easily separated.

Still, there are many reasons to recycle e-waste. For example, there is a growing amount of it—the United Nations found that people generated 44.7 million metric tons of e-waste globally in 2016, and expected that to grow to 52.2 million metric tons by 2021. In addition, precious metals are often scattered within e-waste, although this fact can at times lead to appalling scenarios involving child workers scavenging amidst toxic waste.

"We've developed a throwaway mentality, where we use something until it's worn out or we don't need it or want it any more, and we get rid of it," says study senior author Veena Sahajwalla, a materials scientist and founding director of the Center for Sustainable Materials Research and Technology at the University of New South Wales in Sydney, Australia. "That would be fine if we had unlimited resources and unlimited space for disposal, but we don't."

Previous research showed the careful use of heat could selectively break and reform chemical bonds in e-waste to form new environmentally friendly materials. For instance, mixes of glass and plastic could find use in valuable silicon-loaded ceramics.

"It is very exciting that these waste materials have lot of valuable elements that could be reformed into brand-new products," Sahajwalla says. "To take just one example, some types of e-waste like printed circuit boards contain between 10% and 20% copper, while copper ore only contains up to 3%."

In the new study, researchers investigated the properties of copper and silica compounds often found in old printed circuit boards and computer monitors. They suspected that after these substances were extracted from e-waste, they could get combined to create a durable new hybrid material potentially useful for protecting metal surfaces against corrosion and wear.

First the researchers heated glass and plastic powder from old computer monitor screens and shells to 1,500 degrees C, generating silicon carbide wires 10 to 50 nanometers (billionths of a meter) in diameter. They next combined these ceramic nanowires with copper recovered from ground-up circuit boards, placed the mix on a steel surface, and then heated it up to 1,000 degrees C. This melted the copper to form a thin film 1 micron thick atop the steel. (The scientists noted this width could get adjusted to range from a few nanometers to a few hundred microns.)

This structural bonding of different elements creates new properties that are superior to the parent materials. "Say, for example, the metal structure has a good toughness but a poor hardness. In contrast, a ceramic has a high hardness but it's very brittle," Sahajwalla says. "Combining these two structures together successfully by the judicious choice of temperature after understanding the the raw material can create a completely new hybrid material that has a ceramic-like hardness and metal-like toughness. And surprisingly, all this could be done from waste sources, which can prevent these resources going to a landfill."

The scientists found the micron-thick hybrid layer increased the surface hardness of the steel by about 125%. In addition, microscope images revealed that when this hybrid layer was struck with a nano-sized indenter, it remained firmly bonded to the steel without cracking or chipping.

"For a long time, we have relied on mining to provide the raw materials we need, and we’ve thrown much of our waste into landfill," Sahajwalla says. "In the future, we may be mining those same landfill sites for our resources."

Sahajwalla and her colleague Rumana Hossain detailed their findings online July 13 in the journal ACS Omega.

#DontTouchMyHair : ce mouvement dénonce un problème que beaucoup trop de femmes noires connaissent

Par Mégane Bouron
Ce mouvement consiste à dire stop aux personnes qui s'autorisent à toucher les cheveux des personnes noires ou métisses sans leur demander l'autorisation.⁣

VIDÉO. Médecine naturelle : découvrez la naturopathie

Par Edie & Alexis
Quand de plus en plus de personnes désirent se soigner naturellement, la naturopathie est-elle la solution ? Loïc Ternisien nous en parle.

VIDÉO. TEDx : Entre éco-anxiété et déclics, Pierre Chevelle raconte sa quête de sens

Par Pierre Chevelle
« Si vous aviez un cancer, vous voudriez le savoir ? Et bien là c’est pareil. Si vous saviez que notre civilisation s’effondre, que feriez-vous ? »

Fatiguée du harcèlement de rue lié à sa tenue, elle publie un texte percutant

Par Sophie Renassia
« Je refuse de laisser ces hommes sans respect ni éducation avoir raison de ma liberté de m’habiller. » Un texte percutant pour rappeler l'évidence.

VIDÉO. « Quand on a une IST, tout de suite, on a une étiquette qui est collée »

Par Sophie Renassia
Atteinte d’herpès génital, cette jeune femme a décidé de briser le tabou. Un témoignage précieux autour d'une IST souvent stigmatisée.

VIDÉO. « Il y a des choses qui donnent plus chaud qu’un petit masque » : un spot choc et percutant

Par Mégane Bouron
Le port du masque est un geste quotidien qui sauve des vies. Pour rappeler cet indispensable, Madrid a dévoilé un spot de prévention coup de poing.

Oubliez tout ce que vous pensiez savoir sur le déplacement d’un spermatozoïde : une vidéo édifiante

Par Mégane Bouron
Vous pensiez que le spermatozoïde rejoignait l'ovule à la nage ? Eh bien c'est faux, en réalité, il tourne comme une toupie.

Châlons-en-Campagne : cet artiste transforme les poteaux de sa ville en personnages colorés

Par Sophie Renassia
À Châlons-en-Campagne, les poteaux se sont métamorphosés en personnages pleins de couleurs. Une jolie façon de donner le sourire aux habitants.

VIDÉO. 5 croyances répandues sur les seins enfin démystifiées : un témoignage précieux

Par Mégane Bouron
Stop aux idées reçues sur les seins, cette professeure et philosophe démonte cinq vieilles croyances qui ont la vie dure.

PODCAST. Bergère et maire de Lessay, Stephanie raconte sa transition de Paris à la Normandie

Par Contribution
Stéphanie a quitté sa vie parisienne pour élever des moutons dan le Cotentin. Depuis, elle est devenue maire de Lessay. Retour sur son parcours.

Une messe dans la forme extraordinaire à Ollioules

Par Summorum Pontificum
Une messe dans la forme extraordinaire à Ollioules
Le site Ad Majorem Dei Gloriam, qui recense les messes célébrées en application du Motu Proprio Summorum Pontificum, indique une nouveau lieu de messe à l’ouest de Toulon : Lire la suite ...

Spacecraft of the Future Could Be Powered By Lattice Confinement Fusion

Par Michael Koziol

Nuclear fusion is hard to do. It requires extremely high densities and pressures to force the nuclei of elements like hydrogen and helium to overcome their natural inclination to repel each other. On Earth, fusion experiments typically require large, expensive equipment to pull off.

But researchers at NASA’s Glenn Research Center have now demonstrated a method of inducing nuclear fusion without building a massive stellarator or tokamak. In fact, all they needed was a bit of metal, some hydrogen, and an electron accelerator.

The team believes that their method, called lattice confinement fusion, could be a potential new power source for deep space missions. They have published their results in two papers in Physical Review C.

“Lattice confinement” refers to the lattice structure formed by the atoms making up a piece of solid metal. The NASA group used samples of erbium and titanium for their experiments. Under high pressure, a sample was “loaded” with deuterium gas, an isotope of hydrogen with one proton and one neutron. The metal confines the deuterium nuclei, called deuterons, until it’s time for fusion.

“During the loading process, the metal lattice starts breaking apart in order to hold the deuterium gas,” says Theresa Benyo, an analytical physicist and nuclear diagnostics lead on the project. “The result is more like a powder.” At that point, the metal is ready for the next step: overcoming the mutual electrostatic repulsion between the positively-charged deuteron nuclei, the so-called Coulomb barrier. 

Dr. Theresa Benyo documents the linear accelerator beam conditions during NASA’s lattice confinement fusion experiments while Jim Scheid and Larry Forsley discuss the beam stability data captured during the experiments.
Photo: NASA
Dr. Theresa Benyo documents beam conditions during NASA’s lattice confinement fusion experiments while Jim Scheid and Larry Forsley discuss the beam stability data.

To overcome that barrier requires a sequence of particle collisions. First, an electron accelerator speeds up and slams electrons into a nearby target made of tungsten. The collision between beam and target creates high-energy photons, just like in a conventional X-ray machine. The photons are focused and directed into the deuteron-loaded erbium or titanium sample. When a photon hits a deuteron within the metal, it splits it apart into an energetic proton and neutron. Then the neutron collides with another deuteron, accelerating it.

At the end of this process of collisions and interactions, you’re left with a deuteron that’s moving with enough energy to overcome the Coulomb barrier and fuse with another deuteron in the lattice.

Key to this process is an effect called electron screening, or the shielding effect. Even with very energetic deuterons hurtling around, the Coulomb barrier can still be enough to prevent fusion. But the lattice helps again. “The electrons in the metal lattice form a screen around the stationary deuteron,” says Benyo. The electrons’ negative charge shields the energetic deuteron from the repulsive effects of the target deuteron’s positive charge until the nuclei are very close, maximizing the amount of energy that can be used to fuse.

Aside from deuteron-deuteron fusion, the NASA group found evidence of what are known as Oppenheimer-Phillips stripping reactions. Sometimes, rather than fusing with another deuteron, the energetic deuteron would collide with one of lattice’s metal atoms, either creating an isotope or converting the atom to a new element. The team found that both fusion and stripping reactions produced useable energy.

Larry Forsley examines a CR-39 particle detector used during NASA’s lattice confinement fusion experiments.
Photo: NASA
Bayarbadrakh Baramsai and Philip Ugorowski confer on the neutron spectroscopy system used to detect fusion neutrons.

“What we did was not cold fusion,” says Lawrence Forsley, a senior lead experimental physicist for the project. Cold fusion, the idea that fusion can occur at relatively low energies in room-temperature materials, is viewed with skepticism by the vast majority of physicists. Forsley stresses this is hot fusion, but “We’ve come up with a new way of driving it.”

“Lattice confinement fusion initially has lower temperatures and pressures” than something like a tokamak, says Benyo. But “where the actual deuteron-deuteron fusion takes place is in these very hot, energetic locations.” Benyo says that when she would handle samples after an experiment, they were very warm. That warmth is partially from the fusion, but the energetic photons initiating the process also contribute heat.

There’s still plenty of research to be done by the NASA team. Now they’ve demonstrated nuclear fusion, the next step is to create reactions that are more efficient and more numerous. When two deuterons fuse, they create either a proton and tritium (a hydrogen atom with two neutrons), or helium-3 and a neutron. In the latter case, that extra neutron can start the process over again, allowing two more deuterons to fuse. The team plans to experiment with ways to coax more consistent and sustained reactions in the metal.

Benyo says that the ultimate goal is still to be able to power a deep-space mission with lattice confinement fusion. Power, space, and weight are all at a premium on a spacecraft, and this method of fusion offers a potentially reliable source for craft operating in places where solar panels may not be useable, for example. And of course, what works in space could be used on Earth. 

Will Camera Startup Light Give Autonomous Vehicles Better Vision than Lidar?

Par Tekla S. Perry

In 2013, Rajiv Laroia and Dave Grannan started Light, a company that aimed to disrupt the tiny camera market. The ultimate goal was to provide designs, circuitry, and software to mobile device manufacturers so that smartphones could capture images at qualities that rivaled those taken with bulky, expensive, professional camera lenses. But it turns out the best use of Light’s technology might not be taking better snapshots, but in helping cars see better. 

The technology is built around using an array of inexpensive lenses of varying focal lengths and advanced digital signal processing. Light showcased its approach by
releasing a standalone camera—the 16-lens L16—in 2017, and sold out of its initial production run; the number of units was never made public. 

Part of the magic of Light’s images is the ability to select or change the point of focus after the fact. The multiple camera modules, set slightly apart, also mean that Light cameras can determine a depth value for each pixel in the scene allowing the software to create a three-dimensional map of the objects in the image.

This ability to create a depth map meant that the consumer-targeted L16 got attention from businesses interested in things other than pretty pictures. A rental car company in Germany set up an array of cameras to inspect cars being dropped off for damage; Wayfair experimented with Light’s technology to place furniture within images of rooms. And Light CEO Grannan says the company always hoped to use computational imaging for machine vision as well as consumer cameras.

Nokia 9 PureView
Photo: Nokia

Still, Light continued to focus on going after consumers looking to take better pictures with small devices. And in 2019, the first cellphone camera using Light’s technology hit the market, the five-module Nokia 9 PureView. It didn’t exactly take the world by storm.

“I think our timing was bad,” Grannan says. “In 2019 smartphone sales started to shrink, the product became commoditized, and there was a shift from differentiating on quality and features to competing on price. We had a premium solution, involving extra cameras and an ASIC, and that was not going to work in that environment.”

Fortunately, thanks to Softbank CEO Masayoshi Son, another door had recently opened.

In 2018, looking for additional capital, Light had approached the Softbank Vision Fund about joining its Series D round of investment, a US $121 million infusion that brought total investment in the company to more than $185 million. Son suggested that, in his view, because Light’s technology could effectively allow cameras to see in three dimensions, it could challenge Lidar—which uses pulses of laser light to gauge distances—in the autonomous car market.

“We were intrigued by that,” Grannan says. “We had envisioned multiple vertical markets, but auto wasn’t one of them.”

But, he says, though co-founder and CTO Laroia realized it was theoretically possible to scale the abilities of the company’s depth mapping technology so it could work over the hundreds of meters of range needed by autonomous vehicles, he wasn’t sure it was practical, given the vibration and other challenges a vehicle in motion encounters. Laroia spent about three months convincing himself that the system could be calibrated and the algorithms would work when cameras were separated far enough to make the longer range possible.

With that question settled, Light began an R&D program in early 2019 to further refine its algorithms for use in autonomous vehicles. In mid-2019, with the consumer phone and camera market looking sour, the company announced that it was getting out of that business, and pivoted the entire company to focus on sensing systems for autonomous vehicles.

“We can cover a longer range—up to 1000 meters, compared with 200 or so for lidar,” says Grannan. “The systems we are building can cost a few thousand dollars instead of tens of thousands of dollars. And our systems use less power, a key feature for electric vehicles.”

At the moment, Light’s engineers are testing the first complete prototypes of the system, using an unmarked white van that they are driving around the San Francisco Bay Area. The tests involve different numbers of cameras in the array, with a variety of focal lengths, as the engineers optimize the design. Computation happens on a field-programmable gate array; Light’s engineers expect to have moved the circuitry to an ASIC by early 2021.

The prototype is still in stealth. Grannan says the company expects to unveil it and announce partnerships with autonomous vehicle developers later this year.

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On Solid Ground

Par LEMO

Pagani

The Tower of Pisa is indeed a famous monument. Yet, it is also a monumental error of civil engineering. Built in 1173 with no foundations on a flood plain, the white marble tower started tipping on its southern side even before it was completed. Its peculiar inclination is like a spectacular warning to all builders around the world.

Yet, people have studied the ground under their feet, way before the 12th century. They have done so ever since they started extracting rock, building houses and bridges and digging irrigation systems. At first purely empirical, soil investigation has been rationalised since the 17th century and has given rise to geotechnics, a technoscience combining geology and geomechanics.   

Today, the most frequently used measurement instrument in geotechnics is the penetrometer. “Imagine it as a giant hydraulic press that digs a measurement cone in the ground…” explains Paolo Bruzzi, Pagani Geotechnical’s sales manager. The Italian company, whose factory is based in Piacenza, near Milan, has become a global leader in the field of geotechnical equipment.

Penetrometers render high-fidelity images: “Our equipment detects layers - sand, clay or other - as thin as 10-15 cm.” Enough to make reliable estimates on soil behaviour when building a road or a bridge, digging foundations or simply setting up the pillar of a ski lift.

As for all measurement instruments, the quality of penetrometers depends on their reliability. “The system verifies itself its accuracy after every measurement”, explains Paolo Bruzzi. “Incoherent data would immediately signal that the cone had been damaged. So, we can be sure that our measurements are always absolutely precise.” Furthermore, the cones require mandatory calibration every year, a further warranty of correct measurement. Material and processes are standardised defacto on an international level. The cone sizes, the forces applied, the penetration speed … everything is defined to enable traceability, repeatability and data sharing.

pagani 2

Penetrometer tests can be used for other types of measurements as well. In particular, for seismic measurements.  “In such cases, we stop penetrating after every meter and create a seismic wave from the surface” explains Bruzzi. “Its amplitude and propagation speed is measured by a sensor on the cone, which makes it possible to evaluate the soil’s behaviour in case of earthquakes.”

Anecdotally, the “elastic” soil, isolating the structure from earthquakes, which provoked the tipping of the Tower of Pisa, also protected it from several earthquakes.

The instant results obtained by the penetrometers have greatly contributed to the popularity of these instruments. Carried out in situ, the tests do not require any soil sampling, nor waiting for laboratory analysis results. “They disturb the soil much less than core drilling, so they are less likely to influence the results,” says Paolo Bruzzi.

Whether disturbed or not, ground is not easy to deal with. The equipment must possess huge power to drive in a cone. “In the past, the only solution was using heavy duty trucks, up to 20 tons” recalls Bruzzi. “Such trucks are still used in certain cases and they usually cost in excess of 400,000 euros, require a heavy vehicle driver, an entire team and, since the measurements need to be carried out vertically, a flat, large enough piece of land …”

In a nutshell, a costly and constraining solution. The idea of developing an alternative is how the story of Pagani Geotechnical began.

It all started back in the seventies in Italy. As building requirements were being strengthened, Ermanno Pagani created his geotechnical consulting company. Tests became widely used and the entrepreneur realised that engineers were increasingly using heavy trucks for projects that were much smaller than building bridges or blocks of flats, such as family homes. He wanted to carry out tests with equipment that would be much less disproportionate. Wouldn’t it be possible to have a penetrometer capable of analysing with precision the first 20-25m of soil (deep enough for a large number of projects), but that would be more compact, easy to use and much less costly than geotechnical trucks? Since he couldn’t find anything to meet such needs, he developed his own equipment. As it attracted his customers’ attention, he could foresee the potential market and launched his business. Since then, Pagani Geotechnical stopped being a consultant, and became a manufacturer. His first penetrometers were sold in 1983.

A year later, the company launched its TG 73-200 model, a modular and mobile device. Its mast can be tilted forward and backward enabling measurement even on sloping terrain. It anchors automatically into the ground so that it can exert the necessary thrust, in spite of its modest 3 tons. Handling, anchoring and measurements are automated to such an extent that only a single operator is needed to carry out the tests.

Pagani has put a particular accent on the robustness of the product. “The TG 73-200 was built to be indestructible” laughs Bruzzi. “It withstands all types of “abuse” – very difficult terrain or heavy-handed, clumsy operators!”

Thanks to these “over the top” characteristics, the 73-200 remained Pagani’s high-end model, selling five of them a year. “Its customers are large companies that require no-compromise performance for some highly demanding applications.”  As for other applications, Pagani Geotechnical has taken another step forward.

The TG 63-150, even easier to use, was launched in 1989. It is slightly bigger than 1m by 2m and weighs only a ton. The engineer can transport it himself in a van (no longer a need for a truck and a truck driver) and carry out the measurement on his own. It is a first in its field which simplified the tests and cut the costs considerably. The price (44,000 euros, which is half the price of a 73-200 and close to one tenth of a truck) contributes to broadening the client base – medium-sized companies, consultancy firms, universities, laboratories...

The 63-150 was the first of its kind”, says Paolo Bruzzi. “It had immediate success. With 800 units sold in over 70 countries, it has even become the best-selling compact penetrometer in the world.” It is still Pagani’s best-seller, who sell over sixty of them every year.

The TG 30-20 and 63-100 completed Pagani’s range of penetrometers. The Italian company, still managed by its founder, employs 25 people. Its factory produces between 70 and 80 machines a year and its 800 customers come from almost 90 countries.

Apart from the engines and hydraulic systems, everything is developed and produced “in-house”: accessories, electronic cones, seismic modules, power units… Even its data acquisition systems, including the new CPT AS, launched this spring, fully fitted with LEMO connectors. “This watertight system needs to operate on all terrain, from snow-covered northern countries to the Amazonian rainforest” explains Bruzzi. “We have chosen IP65 certified LEMO connectors for their resistance and compactness, as well as for aesthetic reasons – the excellence of our solutions also derives from design!”

meter

Pagani’s material is robust (its penetrometers are used for “an average of more than 20 years”). Technical components remain stable (“there hasn’t been found anything better for exploring the soil!”). Improvements are made essentially in the electronics system and the accessories. Two or three annual upgrades optimise measurement precision and ease of use. Safety is reinforced to follow the continuous evolution of regulations. Applications have become mobile.

“Many innovations arise from our partnerships with universities and research centres in Italy, Brazil, England or other countries, and, obviously, from feedback from our 800 customers from almost 90 countries, who use our technologies regularly in all possible conditions: in jungles, frozen soil, deserts …”

Pagani, proudly claiming “Made in Italy”, is happy to be associated with high quality. The durability of its machines hasn’t hindered regular sales progress for the last few years. For what reason? There’s been a growing demand for geotechnical tests. “The quality of infrastructures has been improving, requirements have become stricter and additional countries, in particular in emerging economies, have started performing tests.” In short, everything is done to ensure that the Tower of Pisa stays unrivalled.

An Engineer, His Segway, and the ADA: A Tale of the Open Road

Par Allison Marsh

My dad loved to camp, and he wanted to teach his grandson how to pitch a tent, start a fire, and explore nature. Unfortunately, by the time my nephew Liam was born, my dad had already had two major heart attacks, bypass surgery, and had a pacemaker/defibrillator implanted. Hiking over any distance was no longer in the cards for him.

Luckily, my dad’s decline in health seemed to keep pace with the latest breakthroughs in biomedical technology and new pharmaceuticals. He managed to live with congestive heart failure for more than 20 years. Although he died a few years ago, two recent news stories collided last month to remind me how technology and legislation allowed my dad to continue to explore the outdoors and share adventures with his grandson, despite his condition.

The first news of note was the announcement that the Segway is ceasing production. Coverage of this event tended to emphasize how the overhyped, self-balancing two-wheeled personal transportation device failed to live up to expectations. My father would have begged to differ. An engineer by training and an enthusiastic early adopter by temperament, he’d be the first to say that the Segway changed his life.

Dad got his Segway in 2007 when they cost about US $5,000. That is pricey for a toy, but not for a personal assistive device (power wheelchairs also cost thousands of dollars). My mother never begrudged the expense because it kept his world from closing in. He used it every day for work. Stepping aboard, he was able to zip around his 950-square-meter machine shop without getting winded. When he visited clients (mostly large-scale manufacturers), he would load the Segway into his van and then use it to make the rounds on the factory floor. He tricked out his transporter, upgrading the tires to the larger “off road” version that allowed for more maneuverability over uneven terrain. He added detachable saddlebags and hooks. He built a ramp out of scrap wood from a bowling alley to make loading and unloading into his van easier.

The authors father on his Segway, and her nephew Liam on his bike.
Photo: Amanda Skelton
Over a series of weekends, Marsh and his grandson, Liam, tackled all 300 kilometers of the Chesapeake & Ohio Canal.

But his Segway really proved its worth on the weekends. My father, Liam, and my sister Amy trekked the entire 300-kilometer towpath of the Chesapeake & Ohio Canal, him on his Segway, Amy and Liam on bicycles. They did it in segments over many weekends, camping along the route. It turns out the battery life of a Segway is about as far as an 8-year-old boy can bike in a day. Dad would hook his Segway up to the car battery to charge overnight, and they’d be off again in the morning.

During the summer of 2009, he and I went on a cross-continent road trip from Richmond, Va., to Dead Horse, Alaska, because he wanted to drive the AlCan Highway and see the oil fields. We took the northern route across Canada one way and dropped down into the Rockies and across the middle of the Great Plains on the return. Along the way, he raced my dog on the Bonneville Salt Flats, explored the wind-swept lava fields of Craters of the Moon, and watched a perfect sunset at Great Sand Dunes National Park.

The authors father and dog at the Bonneville Salt Flats
Photo: Allison Marsh
Marsh crossed the Bonneville Salt Flats, in Utah, accompanied by Emmeline.

That brings me to the second piece of recent news: the 30th anniversary of the Americans with Disabilities Act. The ADA requires accessible design for all public sites in the United States, including those overseen by the Bureau of Land Management and the National Parks Service. Thanks to the landmark legislation, the worlds Dad could explore opened up enormously. Although there are some limitations—he couldn’t climb down to see the pueblos at Mesa Verde, although he could admire them from the scenic overlook—wheelchair ramps and paved paths allowed him and his Segway to go almost everywhere.

The author, Allison Marsh, at the Valley of the Moon.
Photo: Walter Marsh
The author at Craters of the Moon.

With his Segway, my dad lived a fuller life despite his condition. The Segway was more maneuverable than a wheelchair, with a smaller footprint and turning radius, and it offered easier access to more places. Perhaps most importantly, it allowed him to look people directly in the eye, or even tower slightly above them. Aboard his Segway, he commanded respect, or at least curiosity, from onlookers.

Occasionally, a park ranger would raise an eyebrow at my dad’s Segway and begin to object to its use. My dad would point to the handicapped sticker he proudly displayed on the front of his “assistive device” and launch into a lecture about the ADA and accessibility. He was fortunate to have this marvel of engineering at his disposal, to help him explore, and nothing was going to stop him.

VIDÉO. AlterTour : un tour à vélo participatif pour découvrir les alternatives à travers la France

Par Sarah Vidal
Vous aimez le vélo ? Vous aimez les initiatives écologiques et solidaires ? Vous aimez découvrir la France ? Alors l’AlterTour est fait pour vous !

Pourquoi un pécheur de 20 ans va en Enfer et non un repenti de 30? (2/8)

Par Réponses catholiques

2nd Question : Est-il juste de condamner les pêcheurs non repentis, qui n’ont pas cru en Jesus Christ, à l’enfer éternel pour une vie sur Terre courte de moins de 100 ans. N’était ce pas disproportionné ? Car il est noté à plusieurs endroits dans la bible que nul ne saurait être sauvé par ses œuvres. Donc pour être sauvé, c’est forcément par Christ donc en croyant au Christ et en vivant selon sa volonté. 2nd Question bis : un tueur, voleur etc qui meurt à 20 ans sans connaître Christ va directement en Enfer. Par contre, le tueur, voleur, violeur etc qui à l’âge de 30 ans découvre Christ et se repent avec sincérité gagne le pardon et la vie éternelle. Ce n’est pas juste car le premier n’a pas eu le temps donc l’occasion de se repentir ? (2/8)

Voici la 2e question de la série de 8 que nous avons entamée la semaine dernière. Comme nous le disions, la question est manifestement influencée par une certaine théologie protestante, ce qui fait que les prémisses en sont fausses.

D’une part, il n’est pas exact de dire que la Bible note qu’on ne peut être sauvé par ses œuvres. L’Epître de St Jacques dit même exactement le contraire : «  Mes frères, si quelqu’un prétend avoir la foi, sans la mettre en œuvre, à quoi cela sert-il ? Sa foi peut-elle le sauver ? Supposons qu’un frère ou une sœur n’ait pas de quoi s’habiller, ni de quoi manger tous les jours ; si l’un de vous leur dit : « Allez en paix ! Mettez-vous au chaud, et mangez à votre faim ! » sans leur donner le nécessaire pour vivre, à quoi cela sert-il ? Ainsi donc, la foi, si elle n’est pas mise en œuvre, est bel et bien morte. En revanche, on va dire : « Toi, tu as la foi ; moi, j’ai les œuvres. Montre-moi donc ta foi sans les œuvres ; moi, c’est par mes œuvres que je te montrerai la foi. Toi, tu crois qu’il y a un seul Dieu. Fort bien ! Mais les démons, eux aussi, le croient et ils tremblent. Homme superficiel, veux-tu reconnaître que la foi sans les œuvres ne sert à rien ? N’est-ce pas par ses œuvres qu’Abraham notre père est devenu juste, lorsqu’il a présenté son fils Isaac sur l’autel du sacrifice ? Tu vois bien que la foi agissait avec ses œuvres et, par les œuvres, la foi devint parfaite. Ainsi fut accomplie la parole de l’Écriture : Abraham eut foi en Dieu ; aussi, il lui fut accordé d’être juste, et il reçut le nom d’ami de Dieu. » Vous voyez bien : l’homme devient juste par les œuvres, et non seulement par la foi. Il en fut de même pour Rahab, la prostituée : n’est-elle pas, elle aussi, devenue juste par ses œuvres, en accueillant les envoyés de Josué et en les faisant repartir par un autre chemin ? Ainsi, comme le corps privé de souffle est mort, de même la foi sans les œuvres est morte. » (Jc 2, 14-26)

Ce texte a depuis le début alimenté les débats entre catholiques et Protestants et il embêtait bien Luther, car sa doctrine de la justification ne pouvait pas être plus contredite par la sola Scriptura elle-même, dont il se revendiquait (l’accord entre catholiques et Luthériens de la déclaration d’Augsburg en 1999 a pu résoudre le conflit, mais cela nous entraine loin de la question).

Pour y revenir, si la peine éternelle est disproportionnée par rapport à une vie de moins de 100 ans, est-ce juste d’avoir la vie éternelle dans la Béatitude divine alors qu’on a forcément péché dans notre courte vie ? Pourtant, c’est bien cela que le Seigneur nous promet. Le don, lui, est tout aussi disproportionné mais cela n’a pas l’air d’émouvoir l’auteur de la question. Quant à la damnation éternelle, elle n’est pas question de longueur de vie mais de monstruosité de crimes. L’auteur d’un génocide particulièrement sadique qui a tué des millions de gens doit-il être jugé en fonction de son âge ou en fonction du nombre de ses victimes et de la gravité des tortures subies ? Et quand bien même, qui peut dire qui va en Enfer ou non ? Personne, sinon Dieu.

Quant à la question 2 bis, elle ne tient tout simplement pas debout. 1) le pécheur de 20 ans a moins le temps de pécher que celui de 30, donc, s’il est damné, c’est que, très probablement, ses péchés sont bien plus graves que ceux du plus âgé ; 2) S’il est déjà violeur, voleur, tueur à 20 ans, à peine à la sortie de l’adolescence, cela indique une nature particulièrement viciée, ou alors une très mauvaise influence de son milieu ; 3) dans ce cas, il a subi des contraintes de son entourage et rien ne dit qu’il ira en enfer. Les circonstances atténuantes, ça existe ; 4) Son cas serait bien plus grave s’il connaissait le Christ, car il aurait refusé sa grâce, plutôt qu’un païen qui n’a peut-être qu’une loi morale rudimentaire. Mais même dans ce cas-là, encore une fois, qui peut décréter qui va en Enfer ou non ?

Et surtout, surtout, le lecteur pourrait avec bien plus de profit (re)lire la parabole des Ouvriers de la 11e heure (Mt 20, 1-16), celle du Fils prodigue (Lc 15, 11-32) ou le passage du Bon Larron (Lc 23, 39-49). Oui, Dieu est juste. Mais, dans sa justice, Il fait surtout Miséricorde à qui Il veut, y compris aux repentis de la dernière seconde. Et Il se moque d’une conception étriquée de la justice. Comparaison-poison.

Maladie de Lyme : un vaccin prometteur développé en France

Par Frédéric Ballay

Un vaccin contre la maladie de Lyme en phase d'essai vient de montrer des résultats prometteurs.

Valneva, une société de biotechnologie basée en France, a déclaré que le vaccin produit une réponse immunitaire dans tous les groupes d'âge, avec notamment une réponse particulièrement encourageante chez les personnes âgées les plus touchées par la maladie.

Cet article Maladie de Lyme : un vaccin prometteur développé en France est apparu en premier sur Pepsnews -News positives.

Marcia Baïla : connaissez-vous l’histoire derrière le tube des Rita Mitsouko ?

Par Sophie Renassia
Tout le monde à déjà entendu au moins une fois ce titre mythique du groupe Rita Mitsouko. Mais connaissez-vous réellement l'histoire derrière le tube ?

VIDÉO. Confinement : 25 abonnés de Cache Pas Ta Joie racontent leur expérience

Par Alice Reynaud
25 abonnés de Cache Pas Ta Joie racontent leur confinement et ce qu’ils en ont appris. Une série de 14 épisodes pour tout le mois d’août !

VIDÉO. Se reconvertir ou trouver sa voie grâce au développement personnel

Par Edie & Alexis
Vous manquez de confiance en vous ? Vous voulez changer de voie ? Charlotte Scapin, la fondatrice de Carbone Theory, a quelques conseils pour vous.

Ce photographe met en lumière l’impact que les mots peuvent avoir (10 photos)

Par Mégane Bouron
Cette magnifique série photographique dénonce avec délicatesse et originalité les injustices de notre société. Découverte.

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