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Archive for the ‘engineering’ category: Page 9

Sep 6, 2024

Treating Epidemics as Feedback Loops

Posted by in categories: biotech/medical, engineering, mapping, mathematics

During the worst days of the COVID-19 pandemic, many of us became accustomed to news reports on the reproduction number R, which is the average number of cases arising from a single infected case. If we were told that R was much greater than 1, that meant the number of infections was growing rapidly, and interventions (such as social distancing and lockdowns) were necessary. But if R was near to 1, then the disease was deemed to be under control and some relaxation of restrictions could be warranted. New mathematical modeling by Kris Parag from Imperial College London shows limitations to using R or a related growth rate parameter for assessing the “controllability” of an epidemic [1]. As an alternative strategy, Parag suggests a framework based on treating an epidemic as a positive feedback loop. The model produces two new controllability parameters that describe how far a disease outbreak is from a stable condition, which is one with feedback that doesn’t lead to growth.

Parag’s starting point is the classical mathematical description of how an epidemic evolves in time in terms of the reproduction number R. This approach is called the renewal model and has been widely used for infectious diseases such as COVID-19, SARS, influenza, Ebola, and measles. In this model, new infections are determined by past infections through a mathematical function called the generation-time distribution, which describes how long it takes for someone to infect someone else. Parag departs from this traditional approach by using a kind of Fourier transform, called a Laplace transform, to convert the generation-time distribution into periodic functions that define the number of the infections. The Laplace transform is commonly adopted in control theory, a field of engineering that deals with the control of machines and other dynamical systems by treating them as feedback loops.

The first outcome of applying the Laplace transform to epidemic systems is that it defines a so-called transfer function that maps input cases (such as infected travelers) onto output infections by means of a closed feedback loop. Control measures (such as quarantines and mask requirements) aim to disrupt this loop by acting as a kind of “friction” force. The framework yields two new parameters that naturally describe the controllability of the system: the gain margin and the delay margin. The gain margin quantifies how much infections must be scaled by interventions to stabilize the epidemic (where stability is defined by R = 1). The delay margin is related to how long one can wait to implement an intervention. If, for example, the gain margin is 2 and the delay margin is 7 days, then the epidemic is stable provided that the number of infections doesn’t double and that control measures are applied within a week.

Sep 4, 2024

SpaceX to relocate Starhopper from Boca Chica site

Posted by in categories: engineering, space travel

BOCA CHICA, Texas (ValleyCentral) — A tourist staple at the Boca Chica SpaceX launch site is being relocated.

Many space enthusiasts who have been following SpaceX’s progression in the Rio Grande Valley know that the Starhopper started it all for the space flight company in South Texas.

In 2019, the Starhopper prototype performed its first successful 150 meter flight at the SpaceX Starbase (Boca Chica) site. Since then, the company has continued to test its flight engineering with different SN rockets.

Sep 2, 2024

CAD CAMER on Instagram: ‘❤️3D Gear #gear #technology #mechanical #engineering #mech #tech’

Posted by in category: engineering

848 likes, — cad.camer on July 28, 2024: ‘❤️3D Gear #gear #technology #mechanical #engineering #mech #tech’

Sep 1, 2024

Model Suggests Spewing Metal Nanorods into Mars’ Atmosphere could Warm the Planet by 30K

Posted by in categories: engineering, environmental, nanotechnology, space

A small team of engineers and geophysicists from Northwestern University, the University of Chicago, and the University of Central Florida has found, via modeling, that creating millions of metal nanorods from material on the Martian surface and then blasting them into the atmosphere would be a more efficient way to heat the planet than generating greenhouse gases. Their paper is published in the journal Science Advances.

Science fiction writers have for many years envisioned a future when Mars is made habitable through terraforming techniques, allowing humans to survive without the need for special buildings and spacesuits. Recently, scientists have begun looking at the possibility, though most project ideas are far less ambitious.

Instead of completely transforming the planet, many are looking at simply warming it up a bit to make it more habitable. Most such ideas have centered on releasing greenhouse gases into the atmosphere to capture more heat from the sun. Unfortunately, there are few ingredients on the Martian surface that could be used to create and release such gases.

Aug 30, 2024

Higher-order topological simulation unlocks new potential in quantum computers

Posted by in categories: computing, engineering, quantum physics

Prof Lee said, “Existing breakthrough studies in quantum advantage are limited to highly-specific tailored problems. Finding new applications for which quantum computers provide unique advantages is the central motivation of our work.”

“Our approach allows us to explore the intricate signatures of topological materials on quantum computers with a level of precision that was previously unattainable, even for hypothetical materials existing in four dimensions,” added Prof Lee.

Despite the limitations of current noisy intermediate-scale quantum (NISQ) devices, the team is able to measure topological state dynamics and protected mid-gap spectra of higher-order topological lattices with unprecedented accuracy, thanks to advanced in-house developed error mitigation techniques. This advance demonstrates the potential of current quantum technology to explore new frontiers in material engineering.

Aug 29, 2024

New Biomedical Device Offers Rapid Relief for Chronic Pain Patients

Posted by in categories: biotech/medical, engineering

How can ultrasonic waves be used to treat chronic pain? This is what a recent study published in the journal Pain hopes to address as a team of researchers investigated how a noninvasive treatment known as Diadem, which is a novel biomedical device designed to use ultrasonic waves for combating chronic pain. This study holds the potential to help researchers develop more effective methods at treating chronic pain aside from invasive, surgical treatments.

For the study, the researchers enlisted 20 patients who suffer from chronic pain to participate in trials for the Diadem device or sham stimulations, the latter of which involved auditory masking that has been used in previous research. Each patient received two 40-minute sessions comprised of either the Diadem or sham treatments, followed by being monitored for one week. In the end, the researchers found that 60 percent of patients were received the Diadem treatments reported improved pain management on day 1 and day 7. In contrast, 15 percent and 20 percent of patients who received the sham treatment reported the same for day 1 and day 7, respectively.

“If you or your relatives suffer from chronic pain that does not respond to treatments, please reach out to us; we need to recruit many participants so that these treatments can be approved for the general public,” said Dr. Jan Kubanek, who is an assistant professor in the Department of Biomedical Engineering at the University of Utah and a co-author on the study. “With your help, we think chronic pain can be effectively silenced. And with new pain treatment options, we can tackle the opioid crisis, too.”

Aug 28, 2024

Study of disordered rock salts leads to battery breakthrough

Posted by in categories: engineering, mobile phones, nuclear energy, sustainability, transportation

For the past decade, disordered rock salt has been studied as a potential breakthrough cathode material for use in lithium-ion batteries and a key to creating low-cost, high-energy storage for everything from cell phones to electric vehicles to renewable energy storage.

A new MIT study is making sure the material fulfills that promise.

Led by Ju Li, the Tokyo Electric Power Company Professor in Nuclear Engineering and professor of materials science and engineering, a team of researchers describe a new class of partially disordered rock salt cathode, integrated with polyanions—dubbed disordered rock salt-polyanionic spinel, or DRXPS—that delivers at high voltages with significantly improved cycling stability.

Aug 25, 2024

Voxel building blocks for bioprinting human-compatible organs

Posted by in categories: bioprinting, biotech/medical, chemistry, engineering

A research team at the University of Virginia School of Engineering and Applied Science has developed what it believes could be the template for the first building blocks for human-compatible organs printed on demand.

Liheng Cai, an assistant professor of materials science and engineering and chemical engineering, and his Ph.D. student, Jinchang Zhu, have made biomaterials with controlled mechanical properties matching those of various human tissues.

“That’s a big leap compared to existing bioprinting technologies,” Zhu said.

Aug 25, 2024

For first time, DNA nanotechnology offers both data storage and computing functions

Posted by in categories: biotech/medical, chemistry, computing, engineering, nanotechnology

Researchers from North Carolina State University and Johns Hopkins University have demonstrated a technology capable of a suite of data storage and computing functions – repeatedly storing, retrieving, computing, erasing or rewriting data – that uses DNA rather than conventional electronics. Previous DNA data storage and computing technologies could complete some but not all of these tasks.

“In conventional computing technologies, we take for granted that the ways data are stored and the way data are processed are compatible with each other,” says project leader Albert Keung, co-corresponding author of a paper on the work (Nature Nanotechnology, “A Primordial DNA Store and Compute Engine”). “But in reality, data storage and data processing are done in separate parts of the computer, and modern computers are a network of complex technologies,” Keung is an associate professor of chemical and biomolecular engineering and a Goodnight Distinguished Scholar at NC State.

“DNA computing has been grappling with the challenge of how to store, retrieve and compute when the data is being stored in the form of nucleic acids,” Keung says. “For electronic computing, the fact that all of a device’s components are compatible is one reason those technologies are attractive. But, to date, it’s been thought that while DNA data storage may be useful for long-term data storage, it would be difficult or impossible to develop a DNA technology that encompassed the full range of operations found in traditional electronic devices: storing and moving data; the ability to read, erase, rewrite, reload or compute specific data files; and doing all of these things in programmable and repeatable ways.

Aug 23, 2024

Publisher retracts 350 papers at once

Posted by in categories: computing, engineering, physics

IOP Publishing has retracted a total of 350 papers from two different 2021 conference proceedings because an “investigation has uncovered evidence of systematic manipulation of the publication process and considerable citation manipulation.”

The case is just the latest involving the discovery of papers full of gibberish – aka “tortured phrases” – thanks to the work of Guillaume Cabanac, a computer scientist at the University of Toulouse, Cyril Labbé, of University Grenoble-Alpes and Alexander Magazinov, of Skoltech, in Moscow. The tool detects papers that contain phrases that appear to have been translated from English into another language, and then back into English, likely with the involvement of paper-generating software.

The papers were in the Journal of Physics: Conference Series (232 articles), and IOP Conference Series: Materials Science and Engineering (118 articles), plus four editorials.

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