Tech
Physics-based algorithm enables nuclear microreactors to autonomously adjust power output

A new physics-based algorithm clears a path toward nuclear microreactors that can autonomously adjust power output based on need, according to a University of Michigan-led study published in Progress in Nuclear Energy.
Easily transportable and able to generate up to 20 megawatts of thermal energy for heat or electricity, nuclear microreactors could be useful in remote locations such as rural communities, disaster zones, military bases or even cargo ships, in addition to other applications.
If integrated into an electrical grid, nuclear microreactors could provide stable, carbon-free energy, but they must be able to adjust power output to match shifting demand—a capability known as load following. In large reactors, staff make these adjustments manually, which would be cost-prohibitive in remote areas, imposing a barrier to adoption.
“Many startup and legacy companies in the U.S. are pushing toward near-term and broad deployment of nuclear microreactors, and our work establishes a clear avenue to achieve that in an economically viable way,” said Brendan Kochunas, an associate professor of nuclear engineering and radiological sciences at U-M and corresponding author of the study.
“Our method can help vendors design reactors with autonomous control systems that are safer and more secure.”
This study focused on High-Temperature Gas-Cooled Reactors (HTGR), advanced nuclear reactors that can scale from micro- to large-scale. While based on the Holos-Quad (Gen 2+) model, a HTGR-type microreactor design, the researchers outline a simplified microreactor model that preserves key parameters like power density, inlet coolant temperature, core pressure and flow velocity.
The research team leveraged model predictive control (MPC), a method that predicts future behavior, to optimize control over a defined period of time under certain constraints. Specifically, they developed an MPC controller that optimized the rotation of control drums that surround the microreactor’s central core that decreases power when facing inwards and increases power when facing outwards.
To ensure the model was based in reality and accurately represented the microreactor’s operation, the researchers integrated PROTEUS, a simulation toolset for high-fidelity reactor physics analysis.
When tasked with ramping the power up or down at 20% per minute, their control algorithm stayed within 0.234% of the target. It does all of this without AI, meaning everything about the automated control for load follow operation is grounded in physics and mathematics and readily explainable—an essential feature for passing regulatory review.
Extensive sensitivity tests confirmed their MPC controller works for a wide range of model inputs, validating feasibility for autonomous control.
“The control algorithm’s success and integration with high-fidelity simulation tools demonstrates that we can now design nuclear reactors and their instrumentation and control systems together from the ground up, rather than trying to backfit the I&C (instrumentation and control) systems to a mostly complete reactor design,” said Kochunas.
More information:
Sooyoung Choi et al, High-fidelity microreactor load follow simulations with model predictive control, Progress in Nuclear Energy (2025). DOI: 10.1016/j.pnucene.2025.105889
Citation:
Physics-based algorithm enables nuclear microreactors to autonomously adjust power output (2025, September 23)
retrieved 23 September 2025
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part may be reproduced without the written permission. The content is provided for information purposes only.
Tech
OpenAI Teams Up With Oracle and SoftBank to Build 5 New Stargate Data Centers

OpenAI is planning to build five new data centers in the United States as part of the Stargate initiative, the company announced on Tuesday. The sites, which are being developed in partnership with Oracle and SoftBank, bring Stargate’s current planned capacity to nearly 7 gigawatts—roughly the same amount of power as seven large-scale nuclear reactors.
“AI is different from the internet in a lot of ways, but one of them is just how much infrastructure it takes,” OpenAI CEO Sam Altman said during a press briefing in Abilene, Texas on Tuesday. He argued that the US “cannot fall behind on this” and the “innovative spirit” of Texas provides a model for how to scale “bigger, faster, cheaper, better.”
Three of the new sites, in Shackelford County, Texas, Doña Ana County, New Mexico, and a yet-to-be disclosed location in the Midwest, are being developed in partnership with Oracle. The move follows an agreement Oracle and OpenAI announced in July to develop up to 4.5 gigawatts of US data center capacity on top of what the two companies are already building at the first Stargate facility in Abilene.
OpenAI claims the new data centers, along with a planned 600 megawatt expansion of the Abilene site, will create more than 25,000 onsite jobs, though the number of workers required to build data centers typically dwarfs the amount needed to maintain them afterwards.
The two remaining sites are being helmed by OpenAI and SB Energy, a SoftBank subsidiary that develops solar and battery projects. These are located in Lordstown, Ohio and Milam County, Texas.
Stargate is one of several major US technology infrastructure projects that have been announced since President Donald Trump took office at the start of the year. OpenAI said in January that the $500 billion, 10 gigawatt commitment between the ChatGPT maker, SoftBank, Oracle and MGX would “secure American leadership in AI” and “create hundreds of thousands of American jobs.”
Trump touted the mammoth initiative just two days after he returned to the White House, promising that it would accelerate American progress in artificial intelligence and help the US compete against China and other nations. In July, Trump announced an AI action plan that called for speedy infrastructure development and limited red tape as the US tries to beat other countries in the quest for advanced AI. “We believe we’re in an AI race,” White House AI czar David Sacks said at the time. “We want the United States to win that race.”
OpenAI initially framed Stargate as a “new company” that would be chaired by Softbank CEO Masayoshi Son. Now, however, executives close to the project say it’s an umbrella brand name used to refer to all of OpenAI’s data center projects—except those developed in partnership with Microsoft.
The flagship site in Abilene is primarily owned and operated by Oracle, with OpenAI acting as the primary tenant, according to executives close to the project. The buildout, which is being managed by the data center startup Crusoe, is on track to be completed by mid 2026, sources close to the project say. It is already running on Oracle Cloud Infrastructure and supporting OpenAI training and inference workloads, those sources add.
Tech
Trump’s Tylenol Directive Could Actually Increase Autism Rates, Researchers Warn

For decades, the discussion around autism has been a hotbed of misinformation, misinterpretation, and bad science, ranging from the long-discredited link between the neurodevelopmental condition and vaccines, to newer claims that going gluten-free and avoiding ultra-processed foods can reverse autistic traits.
On Monday night, this specter arose again in the Oval Office, as President Donald Trump announced his administration’s new push to study the causes of autism with claims that the common painkiller Tylenol, otherwise known as acetaminophen, can cause the condition. The FDA subsequently announced that the drug would be slapped with a warning label citing a “possible association.”
David Amaral, professor and director of research at the UC Davis MIND Institute, was among those watching in dismay as the president launched into a diatribe about Tylenol, repeatedly warning pregnant women not to take it, even to treat fevers.
“We heard the president say that women should tough it out,” says Amaral. “I was really taken aback by that, because we do know that prolonged fever, in particular, is a risk factor for autism. So I worry that this admonition to not take Tylenol is going to do the reverse of what they’re hoping.”
The speculation surrounding Tylenol stems from correlations drawn by some studies that have touted an association between use of the painkiller and neurodevelopmental disorders. One such analysis was published last month. The problem, says Renee Gardner, an epidemiologist at the Karolinska Institute in Sweden, is that these studies often reach this conclusion because they don’t sufficiently account for what statisticians describe as “confounding factors”—additional variables related to those being studied that might influence the relationship between them.
In particular, Gardner points out that pregnant women needing to take Tylenol are more likely to have pain, fevers, and prenatal infections, which are themselves risk factors for autism. More importantly, given the heritability of autism, many of the genetic variants that make women more likely to have impaired immunity and greater pain perception, and hence use painkillers like acetaminophen, are also linked to autism. The painkiller use, she says, is a red herring.
Last year, Gardner and other scientists published what is widely regarded within the scientific field as the most conclusive investigation so far on the subject, one which did account for confounding factors. Using health records from nearly 2.5 million children in Sweden, they reached the opposite conclusion to the president: Tylenol has no link to autism. Another major study of more than 200,000 children in Japan, published earlier this month, also found no link.
Doctors are worried that Trump’s claims will have adverse consequences. Michael Absoud, a paediatric neurodisability consultant and a researcher in pediatric neurosciences at King’s College London, says he fears that pregnant women will start using other painkillers with a less well-proven safety profile.
Gardner is concerned that it will also lead to self-blaming among parents, a flashback to the 1950s and 60s, a time when autism was wrongly attributed to emotionally cold “refrigerator mothers.” “It’s making parents of children with neurodevelopmental conditions feel responsible,” she says. “It harks back to the early dark days of psychiatry.”
Tech
How a SIM farm like the one found near the UN threatens telecom networks

The U.S. Secret Service has found and is quietly dismantling a massive network of “SIM farms” across the New York area just as world leaders gather for meetings at the United Nations.
Matt McCool, the special agent in charge of the Secret Service’s New York field office, said agents found multiple sites filled with servers and stacked SIM cards, of which more than 100,000 cards were already active. Though the investigation is ongoing and no arrests have been made, he described it as a well-funded, highly organized enterprise and possibly run by nation-state actors—perpetrators from particular countries.
Officials also warned of the havoc the network could have caused if left intact. McCool compared the potential impact to the cellular blackouts that followed the Sept. 11 attacks and the Boston Marathon bombing, when networks collapsed under strain.
So what are these SIM farms and what are they capable of?
What the tech does
SIM farms are hardware devices that can hold numerous SIM cards from different mobile operators. These devices then exploit voice over internet protocol (VoIP) technology to send and receive bulk messages or calls.
While initially developed for legitimate purposes, such as low cost international calling, the technology has become a cornerstone of organized fraud targeting mass audiences—phishing texts and scam calls.

“Scams have become so sophisticated now. Phishing emails, texts, spoofing caller ID, all of this technology gives scammers that edge,” said Eva Velasquez, president and CEO of the Identity Theft Resource Center.
In this case, the devices were concentrated within 35 miles of the U.N. building. The investigation is ongoing, but McCool said forensic analysis currently believe the system could have been used to send encrypted messages to organized crime groups, cartels and terrorist organizations.
How these farms pose a threat to telecom networks
Anthony J. Ferrante, the global head of the cybersecurity practice at FTI, an international consulting firm, said the photos show a very sophisticated and established SIM farm that could be used for any number of nefarious activities, including the potential to overwhelm cellular networks with millions of calls in just a few minutes.
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This photo provided by the U.S. Secret Service, in New York, Monday, Sept. 22, 2025, shows SIM card packaging that was seized by the agency. Credit: U.S. Secret Service via AP
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This photo provided by the U.S. Secret Service, in New York, Monday, Sept. 22, 2025, shows part of a wall of SIM boxes that were seized by the agency. Credit: U.S. Secret Service via AP
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This photo provided by the U.S. Secret Service, in New York, Monday, Sept. 22, 2025, shows servers on desks at the location where they were seized by the agency. Credit: U.S. Secret Service via AP
“So if you can imagine that type of magnitude on cellular networks, it would just overwhelm them and cause them to shut down,” Ferrante said in an interview. He also notes that it’s possible the system could be used for surveillance operations, given its proximity to the United Nations, “potentially that equipment could be used to either intercept communications, eavesdrop on communications, or actually, clone devices, as well.”
Ferrante, who previously served in key security positions at the White House and the FBI, says he’s awaiting the results of the investigation before drawing any conclusions about the nature of the setup, but he emphasizes that the scale of the operation shows how simple tools can pose real risks to critical infrastructure.
“The masterminds could have set this up a long time ago and be operating from thousands of miles away,” he said. “It’s a stark reminder of how deeply interconnected our world has become, where local vulnerabilities can be exploited globally.”
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Citation:
How a SIM farm like the one found near the UN threatens telecom networks (2025, September 23)
retrieved 23 September 2025
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part may be reproduced without the written permission. The content is provided for information purposes only.
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