Editorial

Esta é a Newsletter Nº 220 que se apresenta com o mesmo formato que as anteriores. Se gostar da Newsletter partilhe-a!

Todas as Newsletters encontram-se indexadas no link.

Esta Newsletter tem os seguintes tópicos:

• Novidades da Semana
• Ciência e Tecnologia
• Documentação
• Projetos Maker

Faz hoje anos que nascia, em 1635, Robert Hooke. Este Físico inglês descobriu a lei da elasticidade, conhecida como lei de Hooke, e inventou a mola de equilíbrio para relógios. Ele era um cientista virtuoso cujo âmbito de pesquisa variava amplamente, incluindo física, astronomia, química, biologia, geologia, arquitectura e tecnologia naval. Ele também inventou ou aperfeiçoou instrumentos meteorológicos, como o barómetro, o anemómetro e o higrómetro.

Faz também anos hoje que nascia, em 1768, Jean-Robert Argand. Este matemático suíço foi um dos primeiros a usar números complexos, que ele aplicou para mostrar que todas as equações algébricas têm raízes. O seu nome está associado ao diagrama de Argand, uma representação geométrica de números complexos como pontos num plano cartesiano, com a porção real do número no eixo do x a parte imaginária no eixo y.

Faz igualmente anos hoje que nascia, 1853, Hendrik Lorentz. Este Físico holandês partilhou (com Pieter Zeeman) o Prémio Nobel de Física em 1902 pela sua teoria da influência do magnetismo sobre os fenómenos da radiação electromagnética. A teoria foi confirmada pelas descobertas de Zeeman e deu origem à teoria da relatividade especial de Albert Einstein. Desde o início, Lorentz fez questão de estender a teoria da electricidade e da luz de James Clerk Maxwell. O seu trabalho fundamental nos campos da óptica e da electricidade revolucionou as concepções da natureza da matéria.

Faz também anos hoje que nascia, em 1906, Sidney Darlington. Este engenheiro electrotécnico norte americano é inventor de uma configuração de transístor em 1953, o par Darlington. Ele avançou o estado da teoria de redes, desenvolvendo a abordagem de síntese de perda de inserção e inventou o radar chirp, as miras de bombardeio e a orientação de armas e foguetes.

Por fim, faz anos hoje que nascia, em 1937, Roald Hoffmann. Este químico americano nascido na Polónia, recebeu, com Fukui Kenichi do Japão, o Prémio Nobel de Química em 1981 pelas suas investigações independentes dos mecanismos de reacções químicas. O seu trabalho visa antecipar teoricamente o curso das reacções químicas. Baseia-se na mecânica quântica (a teoria cujo ponto de partida é que os menores blocos de construção da matéria podem ser considerados tanto partículas quanto ondas), o que tenta explicar como os átomos se comportam. A interacção orbital e as relações de simetria entre moléculas ou partes de moléculas são fundamentais para essa teoria de conservação da simetria orbital em reacções químicas.

Nesta semana que passou a Intel anunciou um sistema neuromórfico de 8 milhões de neurónios, composto por 64 chips de pesquisa Loihi - nome de código Pohoiki Beach - está agora disponível para a comunidade de investigação. Com a Pohoiki Beach, os investigadores podem experimentar o chip de pesquisa inspirado no cérebro da Intel, Loihi, que aplica os princípios encontrados nos cérebros biológicos às arquitecturas de computadores. A Loihi permite que os utilizadores processem informações até 1.000 vezes mais rápido e 10.000 vezes mais eficiente do que CPUs para aplicações especializadas, como codificação esparsa, pesquisa de gráficos e problemas de satisfação de restrições.

Também esta semana ficámos a saber que o sistema de posicionamento global Galileo ficou inoperacional durante vários dias tendo entretanto voltado a ficar operacional. Os utilizadores comerciais já podem ver sinais de recuperação dos serviços de navegação e de hora do Galileo, embora algumas flutuações possam ainda ocorrer. O incidente técnico foi originado por um mau funcionamento do equipamento na infraestrutura terrestre do Galileo, afectando o cálculo das previsões de tempo e órbita, e que são usados para calcular a mensagem de navegação. O mau funcionamento afectou diferentes elementos nas instalações terrestres.

Na Newsletter desta semana apresentamos diversos projetos de maker. É apresentada também a revista Hackspace Magazine de Agosto e o livro "Elements of Programming".

João Alves ([email protected])

O conteúdo da Newsletter encontra-se sob a licença Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

Intel’s Pohoiki Beach, a 64-Chip Neuromorphic System, Delivers Breakthrough Results in Research Tests

"Today, Intel announced that an 8 million-neuron neuromorphic system comprising 64 Loihi research chips — codenamed Pohoiki Beach — is now available to the broader research community. With Pohoiki Beach, researchers can experiment with Intel’s brain-inspired research chip, Loihi, which applies the principles found in biological brains to computer architectures. Loihi enables users to process information up to 1,000 times faster and 10,000 times more efficiently than CPUs for specialized applications like sparse coding, graph search and constraint-satisfaction problems. “We are impressed with the early results demonstrated as we scale Loihi to create more powerful neuromorphic systems. Pohoiki Beach will now be available to more than 60 ecosystem partners, who will use this specialized system to solve complex, compute-intensive problems.” –Rich Uhlig, managing director of Intel Labs Why It’s Important: With the introduction of Pohoiki Beach, researchers can now efficiently scale up novel neural-inspired algorithms — such as sparse coding, simultaneous localization and mapping (SLAM), and path planning — that can learn and adapt based on data inputs. Pohoiki Beach represents a major milestone in Intel’s neuromorphic research, laying the foundation for Intel Labs to scale the architecture to 100 million neurons later this year." [...]

Galileo Initial Services have now been restored

"Galileo Initial Services have now been restored. Commercial users can already see signs of recovery of the Galileo navigation and timing services, although some fluctuations may be experienced until further notice. The technical incident originated by an equipment malfunction in the Galileo ground infrastructure, affecting the calculation of time and orbit predictions, and which are used to compute the navigation message. The malfunction affected different elements on the ground facilities. A team composed of GSA experts, industry, ESA and Commission, worked together 24/7 to address the incident. The team is monitoring the quality of Galileo services to restore Galileo timing and navigation services at their nominal levels." [...]

Samsung Begins Mass Production of Industry’s First 12Gb LPDDR5 Mobile DRAM for Premium Smartphones

"Based on the latest mobile DRAM standard, the new Samsung 12Gb LPDDR5 maximizes the potential of 5G and AI features in future flagships. Samsung Electronics, the world leader in advanced memory technology, today announced that it has begun mass producing the industry’s first 12-gigabit (Gb) LPDDR5 mobile DRAM, which has been optimized for enabling 5G and AI features in future smartphones. The new mobile memory comes just five months after announcing mass production of the 12GB LPDDR4X, further reinforcing the company’s premium memory lineup. Samsung also plans to start mass producing 12-gigabyte (GB) LPDDR5 packages later this month, each combining eight of the 12Gb chips, in line with growing demand for higher smartphone performance and capacity from premium smartphone manufacturers. “With mass production of the 12Gb LPDDR5 built on Samsung’s latest second-generation 10-nanometer (nm) class process, we are thrilled to be supporting the timely launch of 5G flagship smartphones for our customers worldwide,” said Jung-bae Lee, executive vice president of DRAM Product & Technology, Samsung Electronics. “Samsung remains committed to rapidly introducing next-generation mobile memory technologies that deliver greater performance and higher capacity, as we continue to aggressively drive growth of the premium memory market.” Thanks to its industry-leading speed and power efficiency, Samsung’s new mobile DRAM can enable next-generation flagship smartphones to fully leverage 5G and AI capabilities like ultra-high-definition video recording and machine learning, while greatly extending the battery life." [...]

Dual-Interface Secure Microcontroller from STMicroelectronics Boosts Safety and Convenience in Contactless Banking and e-Identification Applications

"Featuring the latest 40nm Flash process as well as enhanced RF technologies, the STMicroelectronics ST31P450 dual-interface secure microcontroller delivers exceptional robustness and performance for contactless applications in banking, identity, transportation, and pay-television. The ST31P450 is built on the proven 32-bit Arm® SecurCore® SC000™ secure processor and meets ISO 7816 and ISO 14443 Type A smart-card and contactless standards. It supports the full range of MIFARE® libraries including MIFARE Classic®, MIFARE Plus®, and MIFARE DESFire®. ST’s 40nm Flash technology creates an ultra-small die for dual-interface use cases such as banking and, with security-enhancing properties, increases safety and fraud prevention. Upgraded RF performance ensures ultra-reliable wireless connections for faster, easier contactless transactions. In addition, the ST31P450 features new low-power cryptographic engines that minimize the energy budget and ensure superior product performance at low RF-field strength while executing cryptographic operations." [...]

Mbed OS 5.13.1 released

"We are pleased to announce the Mbed OS 5.13.1 release is now available. This is the latest patch release based on the feature set that Mbed OS 5.13 introduces. Summary In this release we have added target support for: MTB ublox ODIN W2 and NUCLEO-F413ZH. We have: Introduced a watchdog API to detect system malfunctions and reset the system to recover from them Introduced an API to detect the system reset reason to compliment the watchdog functionality Updated ST CUBE for the STM32F0 series to v1.9.0. This brings: Current ST Cube version in MBED to V1.7.0 CMSIS part update from 2.3.1 to 2.3.3 HAL part update from 1.5.0 to 1.7.0 Replaced our BLE Nordic PAL client implementation. Issues in the GattClient logic have been fixed and previously missing GAT procedures have been implemented: Discover Primary Service by Service UUID Find Included Service Read Using Characteristic UUID Read Multiple Characteristics Queue Prepare Write Execute Write Added Flash support for STM32F0, STM32F1 and STM32F3 devices Enabled tickless mode on nRF52840 Important changes are: 10997 VSCode exporter now uses executables that are installed into the system PATH instead of absolute paths to the compiler executables." [...]

Organic solar cells will last 10 years in space

"Scientists from the Skoltech Center for Energy Science and Technology, the Institute for Problems of Chemical Physics of RAS, and the Department of Chemistry of MSU recently presented solar cells based on conjugated polymers and fullerene derivatives that demonstrated record-high radiation stability. Their ability to withstand gamma radiation of >6,000 Gy raises hopes for their stable operation in near-earth orbit for a period of 10 years or even longer. The results of the study were published in ACS Applied Materials & Interfaces. When the Soviet Union launched the first-ever satellite some 60 years ago, its radio signal transmitted at three frequencies that could be captured anywhere on Earth. However, three weeks later the transmitter went silent, having consumed all the power provided by the onboard batteries, which accounted for the larger part of the satellite’s weight. A lesson was learned from the first launch and all satellites that followed carried solar cells that convert the light energy into electricity to power the onboard electronic systems." [...]

Quantum sensor breakthrough using naturally occurring vibrations in artificial atoms

"A team of scientists, led by the University of Bristol, have discovered a new method that could be used to build quantum sensors with ultra-high precision. When individual atoms emit light, they do so in discrete packets called photons. When this light is measured, this discrete or ‘granular’ nature leads to especially low fluctuations in its brightness, as two or more photons are never emitted at the same time. This property is particularly useful in developing future quantum technologies, where low fluctuations are key, and has led to a surge of interest in engineered systems that act like atoms when they emit light, but whose properties are more easily tailored. These ‘artificial atoms’ as they are known, are typically made from solid materials, and are in fact much larger objects, in which the presence of vibrations is unavoidable, and usually considered to be detrimental. However, a collaborative team, led by the University of Bristol, has now established that these naturally occurring vibrations in artificial atoms can surprisingly lead to an even greater suppression of fluctuations in brightness than that present in natural atomic systems." [...]

Light may increase magnetic memory speeds 1,000 times, decrease electricity consumption

"Internet searches, decade-old emails and on-demand video offerings help contribute to electricity consumption by America’s server farms and data centers amounting to more than 2 percent of the country’s annual total. Those data centers – which operate millions of drives and hold massive amounts of digital data – use some 70 billion kilowatt hours per year of energy. One kWh is enough power to keep a smartphone charged for about a year. At an average cost of 10 cents per kWh, the annual cost of all that power is around $7 billion. Now a method that can potentially reduce energy consumption in magnetic memory devices and improve their speeds is advancing at Purdue University. The method involves a combination of spintronic and photonic materials, where ultrashort laser pulses are employed to generate intense magnetic fields to manipulate the spin orientation of magnetic materials." [...]

Making light behave in useful ways

"By integrating nanoantennas with liquid crystals, A*STAR researchers have created a metasurface that allows fine dynamic control over the properties of light. From holograms to augmented reality devices and optical sensors, a common enabling principle behind these innovations is the ability to precisely manipulate light. Over the years, researchers have created materials that allow them to control how light behaves. A familiar example would be liquid crystals, used in television and mobile phone displays. However, the resolution of liquid crystal-based spatial light modulators leaves much to be desired—each pixel ranges from three to tens of micrometers. Next-generation light detection and ranging (LIDAR) and display technologies require higher resolution and wider steering angles than currently afforded by liquid crystals." [...]

How electronic skin could help people with disabilities

"A University researcher is developing wearable technology that could be used to control devices, receive information and even register sensation. You might not know what they’re called, but you probably use them quite a lot. Virtual buttons, also called soft keys, are on smartphones, ATMs and computer monitors, doing the work of buttons though they are just an image. Virtual buttons are handy and efficient, unless you’re vision impaired, because you can’t actually feel them. Anusha Withana is looking for solutions in what is one of the fastest growing areas of scientific research: electronic skin, “My research is about creating blended interfaces,” he says in the University’s School of Computer Science, where he works. “Meaning technology that can be worn without being noticed.” Wearable technology Working with colleagues, Withana is developing a super-thin, hyper-flexible sticky tape that can have electronic circuits printed onto it." [...]

Automated system generates robotic parts for novel tasks

"When designing actuators involves too many variables for humans to test by hand, this system can step in. An automated system developed by MIT researchers designs and 3-D prints complex robotic parts called actuators that are optimized according to an enormous number of specifications. In short, the system does automatically what is virtually impossible for humans to do by hand. In a paper published today in Science Advances, the researchers demonstrate the system by fabricating actuators — devices that mechanically control robotic systems in response to electrical signals — that show different black-and-white images at different angles. One actuator, for instance, portrays a Vincent van Gogh portrait when laid flat. Tilted an angle when it’s activated, however, it portrays the famous Edvard Munch painting “The Scream.” The researchers also 3-D printed floating water lilies with petals equipped with arrays of actuators and hinges that fold up in response to magnetic fields run through conductive fluids." [...]

Which one is the perfect quantum theory?

"For some phenomena in quantum many-body physics several competing theories exist. But which of them describes a quantum phenomenon best? A team of researchers from the Technical University of Munich (TUM) and Harvard University in the United States has now successfully deployed artificial neural networks for image analysis of quantum systems. Is that a dog or a cat? Such a classification is a prime example of machine learning: artificial neural networks can be trained to analyze images by looking for patterns that are characteristic of specific objects. Provided the system has learned such patterns, it is able to recognize dogs or cats on any picture." [...]

UCLA-developed terahertz sensors work at room temperature, unlike current technology that needs extreme cold

"Light-sensing system could show distant galaxies in unprecedented detail Researchers at the UCLA Samueli School of Engineering have developed an ultra-sensitive light-detecting system that could enable astronomers to view galaxies, stars and planetary systems in superb detail. The system works at room temperature — an improvement over similar technology that only works in temperatures nearing 270 degrees below zero Celsius, or minus 454 degrees Fahrenheit. A paper detailing the advance is published today in Nature Astronomy. The sensor system detects radiation in the terahertz band of the electromagnetic spectrum, which includes parts of the far-infrared and microwave frequencies. The system produces images in ultra-high clarity, and it can detect terahertz waves across a broad spectral range — an improvement of at least 10 times more than current technologies that only detect such waves in a narrow spectral range. Its broad range capabilities could allow it to do observations that currently require several different instruments." [...]

Theory explains ferromagnetic superconductor behavior

"Researchers from France and Russia have offered a theoretical explanation for the behavior of a recently discovered material combining superconducting and ferromagnetic properties. The new theoretical model also predicts so far unobserved effects in materials of this kind. The study was published in Physical Review Letters. Ferromagnetism and superconductivity are, in a way, two opposed tendencies that seemingly cannot coexist in one crystal. Indeed, a superconductor accommodates an electric current with zero resistance. When placed in a magnetic field, such a material expels that field from its bulk in what is known as the Meissner effect." [...]

The best of both worlds: how to solve real problems on modern quantum computers

"Argonne combines quantum and classical approaches to overcome limitations in current quantum computing hardware. In recent years, quantum devices have become available that enable researchers — for the first time — to use real quantum hardware to begin to solve scientific problems. However, in the near term, the number and quality of qubits (the basic unit of quantum information) for quantum computers are expected to remain limited, making it difficult to use these machines for practical applications. A hybrid quantum and classical approach may be the answer to tackling this problem with existing quantum hardware. Researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory and Los Alamos National Laboratory, along with researchers at Clemson University and Fujitsu Laboratories of America, have developed hybrid algorithms to run on quantum machines and have demonstrated them for practical applications using IBM quantum computers (see right rail for description of Argonne’s role in the IBM Q Hub at Oak Ridge National Laboratory [ORNL]) and a D-Wave quantum computer. “This approach will enable researchers to use near-term quantum computers to solve applications that support the DOE mission." [...]

Terahertz technology escapes the cold

"The group of Jérôme Faist in the Institute for Quantum Electronics achieved the first realization of a terahertz quantum cascade laser operating without cryogenic cooling. This feat heralds the widespread use of these devices in practical applications. Terahertz (THz) radiation is a bit like a treasure chest that resists being opened fully. Residing in the electromagnetic spectrum between the infrared and microwave regions, THz radiation combines a range of properties that are ideal with a view to applications. It provides a window to unique spectroscopic information about molecules and solids, it can penetrate non-conducting materials such as textiles and biological tissue, and it does so without ionising — and hence damaging — the object, or subject, under study. This opens up intriguing prospects for non-invasive imaging and non-destructive quality control, among other applications." [...]

Research shows black plastics could create renewable energy

"Research from Swansea University has found how plastics commonly found in food packaging can be recycled to create new materials like wires for electricity – and could help to reduce the amount of plastic waste in the future. While a small proportion of the hundreds of types of plastics can be recycled by conventional technology, researchers found that there are other things that can be done to reuse plastics after they’ve served their original purpose. The research, published in The Journal for Carbon Research, focuses on chemical recycling which uses the constituent elements of the plastic to make new materials. While all plastics are made of carbon, hydrogen and sometimes oxygen, the amounts and arrangements of these three elements make each plastic unique. As plastics are very pure and highly refined chemicals, they can be broken down into these elements and then bonded in different arrangements to make high value materials such as carbon nanotubes. Dr Alvin Orbaek White, a Sêr Cymru II Fellow at the Energy Safety Research Institute (ESRI) at Swansea University said: “Carbon nanotubes are tiny molecules with incredible physical properties." [...]

Atomic motion is captured in 4D for the first time

"Everyday transitions from one state of matter to another — such as freezing, melting or evaporation — start with a process called “nucleation,” in which tiny clusters of atoms or molecules (called “nuclei”) begin to coalesce. Nucleation plays a critical role in circumstances as diverse as the formation of clouds and the onset of neurodegenerative disease. A UCLA-led team has gained a never-before-seen view of nucleation — capturing how the atoms rearrange at 4D atomic resolution (that is, in three dimensions of space and across time). The findings, published in the journal Nature, differ from predictions based on the classical theory of nucleation that has long appeared in textbooks. “This is truly a groundbreaking experiment — we not only locate and identify individual atoms with high precision, but also monitor their motion in 4D for the first time,” said senior author Jianwei “John” Miao, a UCLA professor of physics and astronomy, who is the deputy director of the STROBE National Science Foundation Science and Technology Center and a member of the California NanoSystems Institute at UCLA. Research by the team, which includes collaborators from Lawrence Berkeley National Laboratory, University of Colorado at Boulder, University of Buffalo and the University of Nevada, Reno, builds upon a powerful imaging technique previously developed by Miao’s research group." [...]

Hypertaste: An AI-assisted e-tongue for fast and portable fingerprinting of complex liquids

"The human sense of taste is the result of millennia of evolution. And its astoundingly good at letting us enjoy pleasant foods and beverages as well as warning us against ingesting harmful substances. Man-made sensors, on the other hand, have yet to approach the ease with which our taste buds recognize substances. This is a significant technological gap, as there are many substances out there that we would like to “taste” without actually putting them in our mouth. For the rapid and mobile fingerprinting of beverages and other liquids less fit for ingestion, our team at IBM Research is currently developing Hypertaste, an electronic, AI-assisted tongue that draws inspiration from the way humans taste things. Hypertaste fills a gap in chemical sensing Hypertaste caters to a wide range of industrial and scientific users with a growing need to identify liquids swiftly and reliably without access to high-end laboratories." [...]

Electronic chip mimics the brain to make memories in a flash

"Engineers have mimicked the human brain with an electronic chip that uses light to create and modify memories. RMIT researchers drew inspiration from an emerging tool in biotechnology – optogenetics – to develop a device that replicates the way the brain stores and loses information. Optogenetics allows scientists to delve into the body’s electrical system with incredible precision, using light to manipulate neurons so that they can be turned on or off. The new chip is based on an ultra-thin material that changes electrical resistance in response to different wavelengths of light, enabling it to mimic the way that neurons work to store and delete information in the brain. Research team leader Dr Sumeet Walia said the technology moves us closer towards artificial intelligence (AI) that can harness the brain’s full sophisticated functionality. “Our optogenetically-inspired chip imitates the fundamental biology of nature’s best computer - the human brain,” Walia said." [...]

2D perovskite materials found to have unique, conductive edge states

"A new class of 2D perovskite materials with edges that are conductive like metals and cores that are insulating was found by researchers who said these unique properties have applications in solar cells and nanoelectronics. “This observation of the metal-like conductive states at the layer edges of these 2D perovskite materials provides a new way to improve the performance of next-generation optoelectronics and develop innovative nanoelectronics,” said Kai Wang, assistant research professor in materials science and engineering at Penn State and lead author on the study. Wang and a team of Penn State researchers made the discovery while synthesizing lead halide perovskite materials for use in next generation solar cells. Perovskites, materials with a crystal structure good at absorbing visible light, are an area of focus in developing both rigid and flexible solar cells that can compete commercially with traditional cells made with silicon. These 2D perovskite materials are cheaper to create than silicon and have the potential to be equally efficient at absorbing sunlight. The findings, reported in Science Advances, provide new insights into the charge and energy flow in perovskite materials, important for the continued advancement of the technology, the scientists said." [...]

NIST’s Compact Atomic Gyroscope Displays New Twists

"Researchers at the National Institute of Standards and Technology (NIST) have upgraded their compact atomic gyroscope to enable multitasking measurement capabilities and measure its performance, important steps toward practical applications. Described in a new paper, the quantum gyroscope design and evaluation processes were led by three women — a highly unusual situation in physics and a source of pride for project leader Elizabeth Donley at NIST. Postdoctoral researchers Yun-Jhih Chen and Azure Hansen totally rebuilt the apparatus over the past couple of years. “Not only did we build a simple quantum gyroscope, but this is the first time anyone has demonstrated simultaneous measurement of rotation, rotation angle and acceleration with a single source of atoms,” Donley said. “Other gyroscopes, including the classical ones currently used in phones and planes, can measure only one axis of rotation. This is also the first time we’re reporting a sensitivity for the acceleration and rotation measurements.” The NIST team previously measured rotation with an earlier version of the quantum gyroscope." [...]

Tiny Vibration-Powered Robots Are the Size of the World’s Smallest Ant

"Researchers have created a new type of tiny 3D-printed robot that moves by harnessing vibration from piezoelectric actuators, ultrasound sources or even tiny speakers. Swarms of these “micro-bristle-bots” might work together to sense environmental changes, move materials – or perhaps one day repair injuries inside the human body. The prototype robots respond to different vibration frequencies depending on their configurations, allowing researchers to control individual bots by adjusting the vibration. Approximately two millimeters long – about the size of the world’s smallest ant – the bots can cover four times their own length in a second despite the physical limitations of their small size. “We are working to make the technology robust, and we have a lot of potential applications in mind,” said Azadeh Ansari, an assistant professor in the School of Electrical and Computer Engineering at the Georgia Institute of Technology. “We are working at the intersection of mechanics, electronics, biology and physics." [...]

A Graphene Superconductor That Plays More Than One Tune

"What’s thinner than a human hair but has a depth of special traits? A multitasking graphene device developed by researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). The superthin material easily switches from a superconductor that conducts electricity without losing any energy, to an insulator that resists the flow of electric current, and back again to a superconductor – all with a simple flip of a switch. Their findings were reported today in the journal Nature. “Usually, when someone wants to study how electrons interact with each other in a superconducting quantum phase versus an insulating phase, they would need to look at different materials. With our system, you can study both in one place,” said Guorui Chen, the study’s lead author and a postdoctoral researcher in the lab of Feng Wang, who led the study." [...]

DistME: A Fast and Elastic Distributed Matrix Computation Engine using GPUs developed by DGIST

"A DGIST research team developed a new technology that can process and analyze data differently from the existing technology. Its application is highly looked forward to as it can overcome the limitations of the existing technologies and can process much more data faster. DGIST announced on July 4 that Professor Min-Soo Kim’s team in the Department of Information and Communication Engineering developed the DistME (Distributed Matrix Engine) technology that can analyze 100 times more data 14 times faster than the existing technologies. This new technology is expected to be used in machine learning that needs big data processing or various industry fields to analyze large-scale data in the future. ‘Matrix’ data, which expresses numbers in row and column, is the most widely used form of data in various fields such as machine learning1 and science technology. While ‘SystemML’ and ‘ScaLAPACK’ are evaluated as the most popular technologies to analyze matrix data, but the processing capability of existing technology has recently reached its limits with the growing size of data." [...]

Researchers build transistor-like gate for quantum information processing – with qudits

"Two-qudit gate on a photonic platform achieves massive entangled quantum state Quantum information processing promises to be much faster and more secure than what today’s supercomputers can achieve, but doesn’t exist yet because its building blocks, qubits, are notoriously unstable. Purdue University researchers are among the first to build a gate – what could be a quantum version of a transistor, used in today’s computers for processing information – with qudits. Whereas qubits can exist only in superpositions of 0 and 1 states, qudits exist in multiple states, such as 0 and 1 and 2. More states mean that more data can be encoded and processed. The gate would not only be inherently more efficient than qubit gates, but also more stable because the researchers packed the qudits into photons, particles of light that aren’t easily disturbed by their environment. The researchers’ findings appear in npj Quantum Information." [...]

First programmable memristor computer aims to bring AI processing down from the cloud

"The first programmable memristor computer—not just a memristor array operated through an external computer—has been developed at the University of Michigan. It could lead to the processing of artificial intelligence directly on small, energy-constrained devices such as smartphones and sensors. A smartphone AI processor would mean that voice commands would no longer have to be sent to the cloud for interpretation, speeding up response time. “Everyone wants to put an AI processor on smartphones, but you don’t want your cell phone battery to drain very quickly,” said Wei Lu, U-M professor of electrical and computer engineering and senior author of the study in Nature Electronics. In medical devices, the ability to run AI algorithms without the cloud would enable better security and privacy. Why memristors are good for machine learning The key to making this possible could be an advanced computer component called the memristor." [...]

Researchers Use Nano-Particles to Increase Power, Improve Eye Safety of Fiber Lasers

"Scientists at the U.S. Naval Research Laboratory have devised a new process for using nano-particles to build powerful lasers that are more efficient and safer for your eyes. They’re doing it with what’s called “rare-earth-ion-doped fiber.” Put simply, it’s laser light pumping a silica fiber that has been infused with rare earth ions of holmium. According to Jas S. Sanghera, who heads the Optical Materials and Devices Branch, they have achieved an 85 percent efficiency with their new process. “Doping just means we’re putting rare earth ions into the core of the fiber, which is where all the action happens,” Sanghera explained. “That’s how we’ve produced this world record efficiency, and it’s what we need for a high-energy, eye-safer laser.” According to Colin Baker, research chemist with the Optical Materials and Devices Branch, the lasing process relies on a pump source--most often another laser—which excites the rare earth ions, which then emit photons to produce a high quality light for lasing at the desired wavelength." [...]

NIST’s Quantum Logic Clock Returns to Top Performance

"The quantum logic clock—perhaps best known for showing you age faster if you stand on a stool—has climbed back to the leading performance echelons of the world’s experimental atomic clocks. Physicists at the National Institute of Standards and Technology (NIST) have been quietly upgrading their quantum logic clock design for the past eight years, mainly to reduce errors from unwanted motion of the single aluminum ion (electrically charged atom) that provides the clock “ticks.” As described in Physical Review Letters, the quantum logic clock’s systematic uncertainty (how closely the clock represents the ion’s natural vibrations, or frequency) is 9.4×10−19, the best of any clock worldwide. This means the logic clock would now neither gain nor lose one second in 33 billion years, which is about two-and-a-half times the estimated age of the universe. In this metric, it now outpaces both NIST clocks using neutral atoms trapped in lattices of laser beams, the ytterbium lattice clock and the strontium lattice clock. “The logic clock’s performance is not surprising to me,” project leader David Leibrandt said. “Ion clocks are naturally better isolated from the environment—which is the source of inaccuracy for atomic clocks—than lattice clocks are." [...]

New Unprinting Method Can Help Recycle Paper and Curb Environmental Costs

"Rutgers-led study shows the benefits of removing toner with pulses of intense xenon light Imagine if your printer had an “unprint” button that used pulses of light to remove toner, curbing environmental impacts compared with conventional paper recycling. A Rutgers-led team has created a new way to unprint paper that, unlike laser-based methods, can work with the standard, coated paper used in home and office printers. The new method uses pulses of light from a xenon lamp, and can erase black, blue, red and green toners without damaging the paper, according to a study in the Journal of Cleaner Production. “Our method makes it possible to unprint and then reprint on the same paper at least five times, which is typically as many times paper can be reused with conventional recycling. By eliminating the steps involved in conventional recycling, our unprinting method could reduce energy costs, pollution and greenhouse gas emissions,” said study coauthor Rajiv Malhotra, an assistant professor in the Department of Mechanical and Aerospace Engineering in the School of Engineering at Rutgers University–New Brunswick. Conventional recycling of coated paper is a major contributor to climate change emissions, chemical pollution and energy use, according to the study." [...]

HackSpace magazine #21

"Raspberry Pi 4 model B: It's the new kid on the single board computer block, and it's got more power, speed, memory, IO options and more, yet it's still packed into the same credit card sized space as previous models. We prod and poke one to see just what it's capable of. Get started with laser cutting Build a Tetris-style clock Model mechanisms in Fusion 360 Monitor air quality" [...]

Elements of Programming

"Elements of Programming provides a different understanding of programming than is presented elsewhere. Its major premise is that practical programming, like other areas of science and engineering, must be based on a solid mathematical foundation. The book shows that algorithms implemented in a real programming language, such as C++, can operate in the most general mathematical setting. For example, the fast exponentiation algorithm is defined to work with any associative operation. Using abstract algorithms leads to efficient, reliable, secure, and economical software. " [...]

Mobile Controlled ESP32 Two-Wheel Drive Robot

"Todays project is not going to be based on evive. Today, were going to make yet another smartphone-controlled robot but this time using ESP32. It can move forward, back, right, left, and doesnt need Bluetooth! Were to program it in PictoBlox, our graphical programming software with advanced interaction capabilities and control it using Dabble, our smart project interaction and controller app. You can download PictoBlox from HERE and get Dabble on Google Play. Ready to make the robot?" [...]

Designing a Custom Automotive Controller

"If you're like me, you probably invest too much time into projects that others may think have a very distant payoff, or little payoff at all! Over the last several months, I've been working on such a project. The main project is a Head Up Display (HUD) for my car that will show basic vehicle information (such as speed) alongside in depth data relevant to diagnostics and off road driving. I was dragged into a bit of a rabbit hole when I got hooked on the idea of including a graphic of the vehicle's drivetrain that displays, in real time, exactly which wheels are slipping when traction is poor (this is an AWD vehicle). This rabbit hole lead me to design a control board I'm calling Telemetry Master. Wheel Speed Sensors To create the functionality I wanted, I decided using my vehicle's existing wheel speed sensors was the logical choice." [...]

RGB Matrix Audio Visualizer with Arduino

"Make beautiful music with Adafruit, SparkFun, Arduino and ProtoStax! Create an RGB matrix audio visualizer with Arduino. In this article, I explain how to build an RGB LED matrix audio visualizer, using an Arduino, an RGB LED Matrix Shield, and an Audio Spectrum Analyzer Shield, then put it in an enclosure so that you can have a finished project that you can display by your music system to have a nice light show of your music! For the Audio Spectrum Analysis, I use SparkFun's Spectrum Shield, that uses two MSGEQ7 graphic equalizer display filters, that split a stereo audio input into 7-bands (per channel) and read the amplitude of each using the ADC on your Arduino. It comes with Arduino sample sketches to get started. For the RGB LED Matrix, I use Adafruit's NeoPixel Shield for Arduino, that consists of 40 RGB NeoPixels (Adafruit's terminology for their WS2812 light source)." [...]

Photochromic & Glow-in-the-Dark Clock

"This clock uses a custom built 4-digit 7-segment display made from UV LEDs. In front of the display a screen is placed that consists either of phosphorescent ("glow-in-the-dark") or photochromic material. A push button on the top lights up the UV display which then illuminates the screen for a few seconds so that it starts glowing or changes color which then slowly fades away. This project was inspired by the awesome Glow-In-The-Dark Plot Clock by Tucker Shannon. When I rebuilt his project I gave it a little twist by replacing the glow-in-the-dark screen with one 3D printed from photochromic filament which changes color when exposed to UV light. In the meanwhile I saw that other people had the same idea (see e.g." [...]

Smart Clock with Alexa Interaction

"We designed a smart clock, it can display the time and set an alarm, as well as voice interaction. The clock is a very important part in everyday life. With the development of technology, ordinary clocks cannot meet the current society. Eventually, I successfully embedded the Alexa Voice Service in a clock so that the device not only looked at the time but also the weather, listen to news, etc. " [...]

Change unipolar 28BYJ-48 to bipolar stepper motor

"Now here's something I was not expecting. Previously, I tried to drive this stepper motor with the driver board that came with the motor. My main goal was of course keeping the accuracy of the tiny motor safe and then testing at which speed I could get the maximum torque it could produce. Depending on the driving method, I came up with 300gcm when it was driven using half stepping and 380gcm when I switched to full stepping. Those were actually good results considering that the datasheet predicted these numbers more or less. Now this kind of motor is not really up-to-date with modern technology." [...]

PC Hardware Monitor With Arduino and ST7920 LCD

"There are 2 versions of the project: 4 numeric fieds and 1 graph for CPU load or clock 4 independent graphs for CPU temperature, load, clock and used RAM Parts: Arduino Nano or Arduino Pro Mini with USB to serial adapter ST7920 128x64 LCD Supplies: Parts: Arduino + ST7920" [...]

The Cheapest and Simplest Pulse Counter

"This counter is made only from an ATtiny13 and LED diodes. Did you ever need a cheap and simple (with one digit only) pulse counter? This is the maximum optimization and simplification. Thanks to Charlie Allen. " [...]

A development board for an STM32G081 MCU

"I’ve been an avid user of ST’s F0 series ever since it was launched. The 48MHz Cortex M0 is almost always the perfect MCU for every project that I tend to build and it’s so easy to program and debug that, for me, it’s the default answer to ‘which MCU should I use for this project?’ So when I noticed that ST had launched a ‘G0’ range I just had to have a closer look. " [...]

Logic Game "Columns"

"Hello! Today I would like to share a project to create a simple logical game "Columns". For this we need: One of the most affordable and affordable SPI displays, Arduino Nano, TFT-shield for Arduino Nano (with which we will combine the individual components into a single unit). This shield is the second (lightweight, for Arduino Nano) version of TFT Shield for Arduino Uno, which you can read about here and here and here. Brief description of TFT shield: The size of the board is 64x49 mm, 30-pin connector for connecting Arduino Nano, 14-pin connector for connecting a TFT display 320x240 with an SPI interface (including a touch screen), Connector for microSD card, Connector for the Bluetooth module (HC-06), 20-pin connector for camera OV7670 (as well as others), Mini USB connector, as well as a separate 2-pin connector for power supply 5V. The game itself is very famous, so I will not dwell on the description of its rules." [...]

IoT - Geiger-Muller Counter Using MQTT Protocol

"VERSION 1.1 This project provides a very affordable (25) IoT for Radioactivity long term monitoring using the MQTT transmission protocol widely use in IoT environment. It can be integrated into Home automation applications or Node-RED environments. C-GM Device Features : beta, gamma and X-ray radiation’s counter Max CPM : 65535 (430 µSv/h) Support GM tubes such as SBM-20/19, STS-5 (CTC-5), SI-29-BG, SBT-9/11A, SI-180G, LND-712/7312, etc. 400V GM tube High Voltage Ethernet connection for control and data communication Static IP address support only The interface is basic and made of a LED and one button. Returns current CPM and µSv/h, Max and Average values LED flash on discharges and report failure (steady or fast blinks) External 6V DC pack power (e.g. 6V/1A DC pack available from Amazon, eBay, Banggood, etc.)" [...]

Tracey - Drawing Machine

"Tracey is a servo based panto-graph drawing machine. It consists of two main parts: Controller board Drawing mechanism assembly. Once calibrated correctly Tracey can produce nice fun drawings, slightly shaky but this is the nature of the parts used. There are different fun configurations that Tracey can be used in, some are listed below: Pen on paper drawings. - we will focus on this mode in this Instructable Laser drawing on wood / plastic - using small laser modules UV LED drawing on glow in the dark paint. Drawing on a Magna Doodle." [...]

Yet Another Smart Weather Station, But...

"OK, I know there are so many such weather stations available everywhere, but take a few minutes to see the difference... Low power 2 e-paper displays... but 10 different screens ! ESP32 based accelerometer and temperature / humidity sensors Wifi update 3D printed case and lots of other useful tricks... The main idea is to display various information on both displays depending on the orientation of the box. The case is in the shape of a parallelepipedic box, a paving stone, with a kind of belt that serves as a foot. Supplies: As you can see, the system consists of 2 e-paper screens and a 3D printed box. But there's a lot of things in it: An ESP32 One MPU6050 accelerometer A DHT22 sensor A LiPo battery A PCB to connect the whole thing Homemade duPont threads and a Wi-Fi connection." [...]

Trash Built BT Line Drawing Bot - My Bot

"Hai friends after a long gap about 6 months here i come with a new project. Till the completion of Cute Drawing Buddy V1, SCARA Robot - Arduino i plan for a another drawing bot, main aim is to cover a large space for drawing. So fixed robotic arms can't do it, So I plan for a bot which is able to draw in flat surface. This is version 1 it can able to draw all vector drawing (because stepper used here is very cheap) in any scale. In this tutorial we see not only construction but also deep study of how it draw in very detailed. I listed the supplies in Separate Page so that i able to add images separately." [...]

A simple circuit for measuring electrical current with Arduino

"The current measurement requires the use of an ammeter placed in series with the load. An ideal ammeter has no voltage drop, i.e. it is a short circuit. But most of the current sensors are based precisely on the measurement of the voltage drop on a resistor which, according to Ohm's law, is proportional to the current that passes through it. For what has been said, a good real ammeter must have a very small voltage drop, this in order not to alter the circuit under measurement with its insertion. The sensor I present has a voltage drop of only 50 mV and uses easily available components." [...]

Portable Weather Station for Night Sky Observers

"Light pollution is one of many problems in world. For solve that problem, we need to know how much is night sky polluted with artificial light. Many students with teachers in world try to measure light pollution with expensive sensors. I decided to change my portable luxmeter (for more check previous instructables project Portable Luxmeter ) to weather station with TSL2591 sensor. This sensor is sensitive enough for measure night pollution. Also, I add HTU21D for temperature and humidity measure." [...]

More ESP8266 Hacking - LOHAS LED

"Yes, I have hacked another ESP8266-based device. This time it's the LOHAS WiFi Smart LED lightbulb. These are really quite nice bulbs, and available on Amazon pretty cheaply. Internally there is your typical power supply, and a ring of LEDs. In the center is the main control circuit consisting of an ESP8266, 25Q80 1MB flash chip, and a pair of MY9231 3-channel LED drivers. The LEDs themselves are arranged as a channel of red, a channel of green, a channel of blue, and two channels of white." [...]

Smart Ultrasound Blind Stick

"Nearly 39 million people in the world are blind today. Most of them use a normal white-cane or blind-stick for assistance. In this instructable, we are going to make a smart electronic blind-stick that not only assist in walking blinds but also senses the surrounding environment and alerts if any object/obstacle comes too close. Sound waves follow laws of reflection as that of light. This principle is used in SONAR based range detection and navigation. In this project, we are creating a miniature SONAR module which will fit in a selfie stick( we are modifying it to blind-stick)." [...]

Smart Buoy

"A brief summary of our smart buoy project. We’ll break down the build into separate posts: electronics, 3D print, and dashboard. Hi everyone! This is a brief(ish) summary of our smart buoy project. We’ll break down the technical build into separate posts, to explain: electronics, 3D print, and dashboard. What Does It Do?" [...]

Incubator - INQ

"In this project we will build an affordable incubator which is able to create an internal area with constant temperature and humidity. With an accuracy of +/- 0,2C and +/- 4% relative humidity, you should be able to incubate all kinds of eggs or culture mediums regardless of the outer room temperature. The INQ project was made to offer hobbyists a cheap and easy to build alternative to the expensive industrial incubators.This is part one of the series on how to incubate chicken eggs and keep chickens in your garden. " [...]

BIG POV Fan : HACKED!!

"THIS is a simple , fun , and easy DIY project that kids and adults can enjoy making . POV or persistence of vision projects are interesting and fun projects to build. all you need are a motor led, and some easy to find components, if you liked this project feel free to subscribe to my YouTube channel and support me with nice words. the build materials are: *12 volts motor( medium size) *Arduino nano * magnet *3144 hall effect sensor *8 leds ( high bright led i used white but red is cool too ) *3.7 lipo battery *8 NPN transistors : 2n3904 *lipo battery charging circuit : tp4056 *on of switch : optional NOTE 1: the battery is optional you can go with 9v battery but its heavy and ugly and wont last for long . NOTE2 : in case using 9v batt you should use resistors or you will burn your led" [...]

Low Cost Wireless Sensor Network on 433MHz Band

"What are wireless sensor networks? A simple definition would be: the wireless sensor networks refers to a group of electronic devices distributed on a certain area for monitoring and recording environmental data, that are wirelessly transmitted to a central location to be processed and stored. Nowadays Wireless Sensor Networks can be used in several ways, bellow are just a few examples: Areas of ecological surveillance of forests, rivers, lakes, seas and oceans; Possibility to alert in case o terrorist, chemical, biological, epidemic attacks; Monitoring systems for children, elderly people, patients or people with special needs; Surveillance systems in agriculture and greenhouses; Weather-Forecast monitoring system; Surveillance of city traffic, schools, car parks; And many, many other applications. In this paper I want to show the results of an experiment with wireless sensor networks that have been used for monitoring temperature and humidity data, with a slow and relatively predictable variation. For this experiment I chose to use sensor-senders that I built by my own using affordable modules. The receiver is also DIY, the communication is unidirectional (on the 433 MHz radio band), meaning that the sensors only transmit the data and the central location only receives." [...]

Popsicle Stick Robotic Arm

"Here's how to build a simple robotic arm gripper using just popsicle sticks, an arduino, and a few servos. Supplies: Feel free to use similar materials or whatever you already have. (e.g. cut out cardboard instead of popsicle sticks) Materials: 14 Popsicle Sticks 4 Micro Servos (with their horns and screws) 4 Rotary Potentiometers 1 Half Size Breadboard 1 Arduino Uno 1 6-Volt Battery Pack 26 Jumper Cables Tools: Hot Glue Gun + Hot Glue Sticks Mini precision 1.8 mm screwdriver or other small screwdriver Arduino IDE USB to Arduino Cable" [...]

PC Hardware Monitor With Arduino and Nokia 5110 LCD

"Arduino based PC monitor which displays CPU temperature, load, clock and used RAM CPU load or clock values can be also drawn as a graph. Parts: Arduino Nano or Arduino Pro Mini with USB to serial adapter Nokia 5110 84x48 LCD" [...]

MegaSquirt Digital Dashboard Display

"Project Introduction This is a digital dashboard display project intended to be used with a MegaSquirt2-Extra or MegaSquirt3 ECU (engine control unit). It's 5-inch high-brightness LCD panel and LED strip makes viewing vital car/engine information quick and easy. The firmware currently only has the option of displaying three different screens. One demo screen, and two screen showing some live information from the Megasquirt. The screens are flipped by touching the LCD screen (it's a capacitive touch panel). It's not a simple project but the result is well worth the effort!" [...]

Automatic Road Quality Detector

"This device automatically detects and uploads the location of road hazards, creating a safer driving environment! Introduction Driving on smooth roads is something everyone enjoys and certainly provides for a much safer environment. Rough and jagged roads can be hazardous to those who drive on them, leading to the possibility of more accidents, and most significantly, more deaths. The condition of roadways can vary greatly within both urban and rural cities, and therefore, devices that can aid in quickly identifying hazardous roadways can be extremely valuable to infrastructure engineers striving to increase the safety and quality of their cities. While this prototype device is not fully integrated with urban planners and construction companies, it represents a possible solution to solving one of the primary problems of cities across the world. " [...]

Heart Rate Monitor (Wearable and Wireless Using ECG)

"A rather convenient device to monitor heart rate while running. This is a second iteration of my heart monitoring project, previous one was showing heart beats on a chest, and was connected to uECG via wire. That looks cool, but isn't practical at all - you can't see well how many LEDs exactly are currently on, it's out of your normal view field, and wire connecting it to uECG device creates a lot of problems for the sensor itself, so it basically doesn't work when you run. This version solves all these problems: it is wrist-worn, so you can see it while keeping eyes on the road, and it's wireless, so no distortion of readings, it really works for running and allows you to keep track on heart load. " [...]

Simple DataFlash Board

"This is a small board that plugs into one of the headers on an Arduino Uno or other board to provide 4Mbytes of non-volatile storage It works with either 5V or 3.3V boards, and is based on the low-cost 4Mbyte Winbond W25Q32FVSIG DataFlash chip. It is ideal for applications such as data logging, playing audio samples, and storing text. I also describe a simple DataFlash library to interface to the board. Introduction A DataFlash chip is a simple and low cost way to add non-volatile storage to a microcontroller; chips offering 4Mbytes of storage are available for under 20 pence/cents each from AliExpress or eBay. The downside of using DataFlash chips for non-volatile storage is that the smallest area you can erase is a 4Kbyte sector. If you want to provide the ability to change a single byte at an arbitrary address you have to copy the previous contents of the sector to RAM, or elsewhere on the DataFlash, erase the 4Kbyte sector containing the byte, update the sector copy, and then restore the sector to the DataFlash." [...]

Arduino Datalogger With RTC, Nokia LCD and Encoder

"Parts: Arduino Nano or Arduino Pro Mini Nokia 5110 84x48 LCD DHT11 temperature/humidity sensor DS1307 or DS3231 RTC module with built-in AT24C32 EEPROM Cheap encoder with 3 debouncing capacitors Features: GUI based on Nokia LCD and encoder temperature, humidity, date and time can be stored every 1 to 120 minutes each record is compressed to 39 bitfield only so 32kbit flash (4KB) can fit 819 records optional AT24C256 chip can store even 6553 records deep sleep used to save battery, ATMEGA is woken up by interrupts mainly DHT11 is powered only during measurements powered by single 18650 or other lithium cell a few display "faces" 6 fonts battery level meter data review and graphs min/max with date/time all recorded data dump via serial port in CSV format LCD back light own fast and low resource N5110 library used own low level DHT11 data reading own DS1307, DS3231 and AT24C32 I2C EEPROM handling code the code uses almost all 32KB Arduino flash all internal registers can be stored in external EEPROM or DS1307 internal RAM Data compression Following values are recorded: time (hr,min) date (d,m,y) temperature humidity Above data is compressed to 39-bit bitfield: hr 0..23 5b min 0..59 6b d 1..31 5b m 1..12 4b y 2018..2021 2b temp -40.0..64.0 = 1024values = 10b hum 0..100 7b total 39 bits bits 76543210 byte0 hhhhhmmm byte1 mmmddddd byte2 mmmmyytt byte3 tttttttt byte4 hhhhhhh0 Only 5 bytes are used for 1 record" [...]

Digital Manometer/CPAP Machine Monitor

"Ever wake up in the morning found your CPAP mask is off? This device will alarm you if you have unintentionally removed mask during sleep. CPAP (Continuous Positive Airway Pressure) therapy is the most common form of treatment for Obstructive Sleep Apnea (OSA). For the CPAP therapy patients, it is important to wear the CPAP mask all the time while sleep in order for the therapy to effective, and also to meet the CPAP compliance criteria required by the insurance companies. However many people have issues while adjusting to sleeping with a CPAP mask, including the problem of waking up consistently to find their CPAP mask off. Although many modern CPAP devices are sophisticated enough to differentiate the mask actually being on the person or if the person just turns it on but doesn’t wear the mask, not all of them have alarm or alarm loud enough to wake up the patient when the CPAP mask is removed, or there is a large air leak." [...]