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  • ✇Semiconductor Engineering
  • Research Bits: Aug. 5Jesse Allen
    Measuring temperature with neutrons Researchers from Osaka University, National Institutes for Quantum Science and Technology, Hokkaido University, Japan Atomic Energy Agency, and Tokamak Energy developed a way to rapidly measure the temperature of electronic components inside a device using neutrons. The technique, called ‘neutron resonance absorption’ (NRA), examines neutrons being absorbed by atomic nuclei at certain energy levels to determine the properties of the material. After being gener
     

Research Bits: Aug. 5

5. Srpen 2024 v 09:01

Measuring temperature with neutrons

Researchers from Osaka University, National Institutes for Quantum Science and Technology, Hokkaido University, Japan Atomic Energy Agency, and Tokamak Energy developed a way to rapidly measure the temperature of electronic components inside a device using neutrons.

The technique, called ‘neutron resonance absorption’ (NRA), examines neutrons being absorbed by atomic nuclei at certain energy levels to determine the properties of the material. After being generated using high-intensity laser beans, the neutrons were then decelerated to a very low energy level before being passed through the sample, in this case plates of tantalum and silver. The temporal signal of the NRA was altered in a predictable manner when the sample material’s temperature was changed.

“This technology makes it possible to instantaneously and accurately measure temperature,” said Zechen Lan of Osaka University, in a statement. “As our method is non-destructive, it can be used to monitor devices like batteries and semiconductor devices.”

The technique can acquire temperature data in a window of 100 nanoseconds, and the measurement device itself is about a tenth of the size of similar equipment.

“Using lasers to generate and accelerate ions and neutrons is nothing new, but the techniques we’ve developed in this study represent an exciting advance,” added Akifumi Yogo of Osaka University, in a statement. “We expect that the high temporal resolution will allow electronics to be examined in greater detail, help us to understand normal operating conditions, and pinpoint abnormalities.” [1]

Mapping heat transfer

Researchers from the University of Rochester applied optical super-resolution fluorescence microscopy techniques used in biological imaging to map heat transfer in electronic devices using luminescent nanoparticles.

By applying highly doped upconverting nanoparticles to the surface of a device, the researchers were able to achieve super-high resolution thermometry at the nanoscale level from up to 10 millimeters away.

Rochester researchers demonstrated their super-high resolution thermometry techniques on an electrical heater structure that the team designed to produce sharp temperature gradients. (Credit: University of Rochester / J. Adam Fenster)

“The building blocks of our modern electronics are transistors with nanoscale features, so to understand which parts of overheating, the first step is to get a detailed temperature map,” said Andrea Pickel, an assistant professor from the University of Rochester’s Department of Mechanical Engineering, in a release. “But you need something with nanoscale resolution to do that.”

The researchers demonstrated the technique using an electrical heater structure designed to produce sharp temperature gradients. To improve the process, the team hopes to lower the laser power used and refine the methods for applying layers of nanoparticles to the devices. [2]

ML for predicting thermal properties

Researchers from MIT, Argonne National Laboratory, Harvard University, the University of South Carolina, Emory University, the University of California at Santa Barbara, and Oak Ridge National Laboratory propose a new machine learning framework that provides much faster prediction of phonon dispersion relations, an important measurement for determining the thermal properties of a material and how heat moves through semiconductors and insulators.

Heat-carrying phonons have an extremely wide frequency range, and the particles interact and travel at different speeds. “Phonons are the culprit for the thermal loss, yet obtaining their properties is notoriously challenging, either computationally or experimentally,” said Mingda Li, associate professor of nuclear science and engineering at MIT, in a release.

The researchers started with a graph neural network (GNN) that converts a material’s atomic structure into a crystal graph comprising multiple nodes, which represent atoms, connected by edges, which represent the interatomic bonding between atoms.

To make it suitable for predicting phonon dispersion relations, they created a virtual node graph neural network (VGNN) by adding a series of flexible virtual nodes to the fixed crystal structure to represent phonons. This enabled the VGNN to skip many complex calculations when estimating phonon dispersion relations, making it a more efficient method than a standard GNN.

Li noted that a VGNN could be used to calculate phonon dispersion relations for a few thousand materials in a few seconds with a personal computer. The technique could also be used to predict challenging optical and magnetic properties. [3]

References

[1] Lan, Z., Arikawa, Y., Mirfayzi, S.R. et al. Single-shot laser-driven neutron resonance spectroscopy for temperature profiling. Nat Commun 15, 5365 (2024). https://doi.org/10.1038/s41467-024-49142-y

[2] Ziyang Ye et al., Optical super-resolution nanothermometry via stimulated emission depletion imaging of upconverting nanoparticles. Sci. Adv. 10, eado6268 (2024) https://doi.org/10.1126/sciadv.ado6268

[3] Okabe, R., Chotrattanapituk, A., Boonkird, A. et al. Virtual node graph neural network for full phonon prediction. Nat Comput Sci 4, 522–531 (2024). https://doi.org/10.1038/s43588-024-00661-0

The post Research Bits: Aug. 5 appeared first on Semiconductor Engineering.

  • ✇Latest
  • Operation Rolling Thunder: The Shocking Truth Behind Spartanburg's Traffic StopsDaryl James, Rob Johnson
    In Spartanburg County, South Carolina, on Interstate 85, police officers stop vehicles for traveling in the left lane while not actively passing, touching the white fog line, or following too closely. This annual crackdown is called Operation Rolling Thunder, and the police demand perfection. Any infraction, no matter how minor, can lead to a roadside interrogation and warrantless search. However, a 21-month fight for transparency shows participa
     

Operation Rolling Thunder: The Shocking Truth Behind Spartanburg's Traffic Stops

5. Srpen 2024 v 14:00
An illustration of a police officer's silhouette against images of money | Illustration: Lex Villena; Midjourney

In Spartanburg County, South Carolina, on Interstate 85, police officers stop vehicles for traveling in the left lane while not actively passing, touching the white fog line, or following too closely. This annual crackdown is called Operation Rolling Thunder, and the police demand perfection.

Any infraction, no matter how minor, can lead to a roadside interrogation and warrantless search. However, a 21-month fight for transparency shows participating agencies play loose with South Carolina's Freedom of Information Act (FOIA), which requires the government to perform its business in an "open and public manner."

Motorists must follow state laws with exactness. But the people in charge of enforcement give themselves a pass.

Deny, Deny, Deny

The drawn-out FOIA dispute started on October 11, 2022, less than one week after a five-day blitz that produced nearly $1 million in cash seizures. Our public-interest law firm, the Institute for Justice, requested access to incident reports for all 144 vehicle searches that occurred during the joint operation involving 11 agencies: The Cherokee, Florence, Greenville, and Spartanburg County sheriff's offices; the Duncan, Gaffney, and Wellford police departments; the South Carolina Highway Patrol, Law Enforcement Division, and State Transport Police; and the U.S. Department of Homeland Security.

Our intent was simple. We wanted to check for constitutional violations, which can multiply in the rush to pull over and search as many vehicles as possible within a set time frame. South Carolina agencies have conducted the operation every year since 2006, yet no one has ever done a systematic audit.

Rather than comply with its FOIA obligation, Spartanburg County denied our request without citing any provision in the law. We tried again and then recruited the help of South Carolina resident and attorney Adrianne Turner, who filed a third request in 2023.

It took a lawsuit to finally pry the records loose. Turner filed the special action with outside representation.

Key Findings

The incident reports, released in batches from March through July 2024, show why Spartanburg County was eager to prevent anyone from obtaining them.

  • Over 72 percent of vehicle searches during Operation Rolling Thunder in 2022 produced nothing illegal. Officers routinely treated innocent drivers like criminals.
  • Carrying any amount of cash is legal, but officers treated currency as contraband. The records describe no single case in which officers found a large amount of cash and did not seize it. All money was presumed dirty.
  • Officers pressured property owners to sign roadside abandonment forms, giving up claims to their cash on the spot.
  • South Carolina residents mostly got a pass. Officers focused on vehicles with out-of-state plates, rental cars, and commercial buses. Over 83 percent of the criminal suspects identified during warrantless searches lived out of state. Nearly half were from Georgia.
  • Black travelers were especially vulnerable. Nearly 74 percent of the suspects identified and 75 percent of the people arrested were black. This is more than triple the South Carolina black population of 25 percent.

Working in the Shadows

While these records shine a light on police conduct, still more secrets remain.

By policy, the Spartanburg County Sheriff's Office and partner agencies do not create incident reports for every search. They only document their "wins" when they find cash or contraband. They do not document their "losses" when they come up empty.

Thanks to this policy, Spartanburg County has no records for 102 of the 144 searches that occurred during Operation Rolling Thunder in 2022. Nowhere do officers describe how they gained probable cause to enter the vehicles where nothing was found. The police open and close investigations and then act like the searches never happened.

This leaves government watchdogs in the dark—by design. They cannot inspect public records that do not exist. Victims cannot cite them in litigation. And police supervisors cannot review them when evaluating job performance.

Even if body camera video exists, there is no paper trail. This lack of recordkeeping undercuts the intent of FOIA. Agencies dodge accountability by simply not summarizing their embarrassing or potentially unconstitutional conduct.

The rigged system is rife with abuse. Available records show that officers routinely order drivers to exit their vehicles and sit in the front seat of a patrol car. If people show signs of "labored breathing," "nervousness," or being "visibly shaken," the police count this toward probable cause.

Officers overlook that anxiety is normal when trapped in a police cruiser without permission to leave. Even people who value their Fourth Amendment right to be "secure in their persons, houses, papers, and effects, against unreasonable searches and seizures" can break under pressure and consent to a search.

If travelers refuse, officers can bring K9 units to the scene for open-air sniffs. Having no drugs in the vehicle does not always help. False positives occurred during Operation Rolling Thunder, but the lack of recordkeeping makes a complete audit impossible.

Intimidation, harassment, and misjudgment are easily hidden. The police tell travelers: "If you have nothing to hide, you should let us search." But when the roles are reversed and the public asks questions, agencies suddenly want to remain silent.

The post Operation Rolling Thunder: The Shocking Truth Behind Spartanburg's Traffic Stops appeared first on Reason.com.

  • ✇Latest
  • The Budget Deal Is Overflowing With $12 Billion of EarmarksEric Boehm
    Voters in California went to the polls this week for a primary election that's the first step towards picking a permanent replacement for the late Sen. Dianne Feinstein, who died nearly six months ago. In Washington, meanwhile, Feinstein is still wielding influence from beyond the grave. Her name is attached to 256 different earmarks included in the budget bill working its way through Congress this week. Those pork projects will cost taxpayers ab
     

The Budget Deal Is Overflowing With $12 Billion of Earmarks

6. Březen 2024 v 20:35
Money falls against a white background | Photo 11098381 © Dibrova | Dreamstime.com

Voters in California went to the polls this week for a primary election that's the first step towards picking a permanent replacement for the late Sen. Dianne Feinstein, who died nearly six months ago.

In Washington, meanwhile, Feinstein is still wielding influence from beyond the grave. Her name is attached to 256 different earmarks included in the budget bill working its way through Congress this week. Those pork projects will cost taxpayers about $1.1 billion if the bill passes in its current form, the Washington Examiner reported Tuesday.

And that only scratches the surface. The partial budget deal—which contains six of the 12 appropriations bills that make up the discretionary portion of the annual federal budget—is overflowing with earmarks to fund lawmakers' pet projects. All told, there are more than 6,000 earmarks in the bill, costing taxpayers more than $12.7 billion, according to Sen. Mike Lee (R–Utah), who has urged Republicans to vote against the package.

Many of the earmarks in the package seem like things that would be better funded by local or state taxpayers, who at least might stand to benefit from projects like new sewer systems, new runways and other upgrades for tiny rural airports, and a plethora of highway projects. Some are truly head-scratching, like Sen. Tammy Baldwin's (D–Wis.) $1.4 million earmark for a solar energy project in Wisconsin, one of the places in America least well suited for a solar farm.

Plenty of others make no sense for the public to be funding at all. Like a $3.5 million earmark secured by Sen. Debbie Stabenow (D–Mich.) for The Parade Company, which runs Detroit's annual Thanksgiving Day parade. Or the $2.5 million earmark that will help build a new kayaking facility in Franklin, New Hampshire, curtsey of Sen. Jeanne Shaheen (D–N.H.), as well as $2.7 million line item to help build a bike park in White Sulfur Springs, West Virginia, a town with a population of less than 2,300 people.

For that amount of money, "you could buy EVERY resident a $1,200+ bike" Sen. Rick Scott (R–Fla.), who has become a vocal critic of the earmarks in the bill, posted on X (formerly Twitter). "There's no way they need this much of YOUR money for this."

The same could be said for several Republican-based earmarks too. Sen. Lindsey Graham (R–S.C.) has inserted at least eight earmarks into the bill, forcing federal taxpayers to put up more than $33 million for things most will never use, like a new trail at Coastal Carolina University and an ROTC facility at the University of South Carolina. Among the dozens of earmarks inserted by Sen. Lisa Murkowski (R–Alaska), perhaps the strangest is the $4 million grant for the "Alaska King Crab Enhancement Project."

Wait, you might be thinking, didn't Congress ban the use of earmarks when tea party-era Republicans controlled the government? Yep, they did. But like fiscal responsibility and concern about America's ballooning entitlement costs, those efforts to limit pork barrel spending are now distant memories. Democrats voted to reinstate earmarks in 2021, and Republicans soon followed suit.

To Congress' credit, earmarks are now handled more transparently than they used to be—which is why you can view the full list of earmarks included in the budget bills here.

Still, some things never change. Earmarks remain expensive, wasteful exercises in cronyism—and with the country $34 trillion in debt, Congress should not be putting taxpayers on the hook for frivolous handouts to politically connected friends.

The post The Budget Deal Is Overflowing With $12 Billion of Earmarks appeared first on Reason.com.

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