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05/19/2016 : 139304
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With New Technology, You Can Find Hazardous Gases in Seconds
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Posted by Okachinepa on 01/12/2025 @
Courtesy of SynEvol
Credit: Florian Sterl
A novel technique for quickly and accurately detecting and identifying tiny levels of gases has been revealed by researchers. This novel technique, called coherently regulated quartz-enhanced photoacoustic spectroscopy, may open the door for extremely sensitive, real-time sensors that are employed in fields such as chemical process control, medical breath analysis, and environmental monitoring.
According to Simon Angstenberger, the research team leader from the University of Stuttgart in Germany, "since most gases are present in small amounts, detecting gases at low concentrations is important in a wide variety of industries and applications." "Our method is not restricted to any particular gas and does not require prior knowledge of the gas that might be present, in contrast to other trace gas detection techniques that rely on photoacoustics."
In just three seconds, the researchers showcased their approach by recording the entire methane spectrum (3050 to 3450 nanometers), which normally takes about half an hour.
"By identifying greenhouse gases like methane, which is a powerful contributor to climate change, this new technology could be used for climate monitoring," Angstenberger added. "It also has potential applications in chemical production plants for process control and the detection of toxic or flammable gas leaks, as well as in early cancer detection through breath analysis."
By examining each gas's distinct light absorption properties, spectroscopy may identify compounds, including gases, by creating a "fingerprint" for each one. Nevertheless, rapid detection of low gas concentrations necessitates not only a fast-tuning laser but also a very sensitive detection mechanism and accurate electrical control of the laser timing.
The researchers employed a laser with a very fast controllable wavelength in the new study that was created recently by partners at Stuttgart Instruments GmbH, a university spin-off. Additionally, they used QEPAS, or quartz-enhanced photoacoustic spectroscopy, as the sensitive detection method. By electronically detecting the vibrations of a quartz tuning fork at a resonance frequency of 12,420 Hz, which is caused by a laser pulsed at the same frequency, this spectroscopy method detects gas absorption. The fork's prongs move as a result of the laser's quick pulses heating the gas between them, producing a detectable piezoelectric voltage.
Although the tuning fork's high quality factor, which causes it to ring for a long time, enables us to detect tiny concentrations using what scientists refer to as resonant improvement, it restricts the rate of acquisition," Angstenberger clarified. This is because the fork continues to move when we switch wavelengths to get the molecule's fingerprint. We must somehow halt the movement in order to measure the next feature.
The researchers came up with a method known as coherent control to get around this issue. This required keeping the laser output power constant while adjusting the pulse time by precisely half a fork oscillation cycle. As a result, when the prongs of the fork move inward, the laser pulse reaches the gas between them. By acting against the prongs' movement as the gas heats up and expands, this method reduces the fork oscillation. The fork stops shaking after a few hundred microseconds of laser light flashing, at which point the subsequent measurement can be taken.
Angstenberger stated, "Ultra-fast identification of gases using their vibrational and rotational fingerprints is made possible by adding coherent control to QEPAS." "We can achieve real-time monitoring with a broad laser tuning range of 1.3 to 18 µm, making it capable of detecting virtually any trace gas, unlike traditional setups limited to specific gases or single absorption peaks."
Using a commercially available QEPAS gas cell and a laser created by Stuttgart Instruments, the researchers tested the new technique by analyzing a pre-calibrated methane mixture that had 100 parts per million of methane in the gas cell. They demonstrated that while the spectral fingerprint is blurred by scanning too quickly with standard QEPAS, it remains distinct and unaltered when using the coherent control approach.
In order to ascertain the new technology's maximum speed and lowest sensing concentration, the researchers intend to investigate its limitations in the future. Additionally, they hope to utilize it to sense several gasses simultaneously.
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Microsoft Files Lawsuit Against Hacking Group Using Azure AI
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Posted by Okachinepa on 01/12/2025 @
Courtesy of SynEvol
Credit: Ravie Lakshmanan
A "foreign-based threat–actor group" is being sued by Microsoft for using a hacking-as-a-service infrastructure to purposefully circumvent the security measures of its generative artificial intelligence (AI) services and create offensive and damaging content.
The threat actors "developed sophisticated software that exploited exposed customer credentials scraped from public websites," according to the tech giant's Digital Crimes Unit (DCU), and "sought to identify and unlawfully access accounts with certain generative AI services and purposely alter the capabilities of those services."
After using these services, like Azure OpenAI Service, the enemies made money by selling the access to other malevolent actors and giving them comprehensive instructions on how to utilize these specialized tools to produce damaging content. According to Microsoft, the behavior was identified in July 2024.
In order to stop such conduct from happening again, the Windows manufacturer claimed it has since removed the threat-actor group's access, strengthened its security, and put additional countermeasures in place. Additionally, it claimed to have secured a court order to take control of a website ("aitism[.]net") that was essential to the group's illegal activity.
The widespread use of AI technologies such as OpenAI ChatGPT has also resulted in threat actors misusing them for nefarious purposes, such as creating malware or illegal content. Microsoft and OpenAI have consistently revealed that their services are being used for disinformation campaigns, translation, and reconnaissance by nation-state entities from China, Iran, North Korea, and Russia.
According to court filings, the operation was carried out by at least three unidentified persons who used customer Entra ID authentication details and stolen Azure API credentials to hack Microsoft servers and exploit DALL-E to produce malicious photos in violation of the company's acceptable use policy. Their services and tools are thought to have been employed for similar reasons by seven other parties.
Although it is currently unknown how the API keys are obtained, Microsoft said that the defendants committed "systematic API key theft" from a number of clients, including a number of American businesses, some of which are based in Pennsylvania and New Jersey.
"Using stolen Microsoft API Keys that belonged to U.S.-based Microsoft customers, defendants created a hacking-as-a-service scheme – accessible via infrastructure like the 'rentry.org/de3u' and 'aitism.net' domains – specifically designed to abuse Microsoft's Azure infrastructure and software," according to the filing.
A GitHub project that has since been deleted claims that de3u is a "DALL-E 3 frontend with reverse proxy support." The aforementioned GitHub account was established on November 8, 2023.
Following the capture of "aitism[.]net," the threat actors allegedly attempted to "cover their tracks, including by attempting to delete certain Rentry.org pages, the GitHub repository for the de3u tool, and portions of the reverse proxy infrastructure."
Microsoft saw that in order to illegally create thousands of damaging images using text prompts, the threat actors used de3u and a custom reverse proxy service known as the oai reverse proxy to conduct Azure OpenAl Service API requests using the stolen API keys. What kind of offensive imagery was produced is unknown.
The purpose of the server-based oai reverse proxy service is to route user computer connections into the Azure OpenAI Service via a Cloudflare tunnel, then return the replies to the user's device.
"The de3u software allows users to issue Microsoft API calls to generate images using the DALL-E model through a simple user interface that leverages the Azure APIs to access the Azure OpenAI Service," Redmond stated.
In order to send queries that are intended to resemble authentic Azure OpenAPI Service API calls, the defendants' de3u application uses undocumented Microsoft network APIs to interface with Azure servers. Additional authenticating information and stolen API keys are used to validate these requests.
The use of proxy services to gain unauthorized access to LLM services was brought to light by Sysdig in May 2024 in relation to an LLMjacking attack campaign that used stolen cloud credentials to target AI offerings from Anthropic, AWS Bedrock, Google Cloud Vertex AI, Microsoft Azure, Mistral, and OpenAI. The actors then sold the access to other parties.
In order to accomplish their shared illicit goals, defendants have carried out the operations of the Azure Abuse Enterprise through a coordinated and ongoing pattern of illegal action," Microsoft stated.
"The defendants' illicit behavior pattern extends beyond their attacks on Microsoft. Other AI service providers have been the target and victims of Azure Abuse Enterprise, according to evidence Microsoft has discovered so far.
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AI Innovation Solves Supercomputer Math on Desktop Computers in a Matter of Seconds
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Posted by Okachinepa on 01/07/2025 @
Courtesy of SynEvol
Credit: Johns Hopkins University
The ability to model complicated systems, such as how vehicles deform in collisions, how spacecraft handle harsh circumstances, or how bridges bear stress, at thousands of times faster than previously feasible is being made possible by a breakthrough in artificial intelligence. Massive mathematical problems that formerly required the power of supercomputers can now be solved by personal computers because to this invention.
The new AI framework provides a flexible and effective way to forecast answers to difficult mathematical problems. These formulas are essential for simulating phenomena that are frequently seen in engineering and design tests, such as fluid flow or the behavior of electrical current in different geometries.
The system, known as DIMON (Diffeomorphic Mapping Operator Learning), resolves partial differential equations, which are common mathematical problems found in almost all engineering and scientific study. Researchers can convert real-world systems or processes into mathematical depictions of how environments or items will change across time and space by using these equations.
"This is a solution that we think will generally have a massive impact on various fields of engineering because it's very generic and scalable," said Natalia Trayanova, a professor of biomedical engineering and medicine at Johns Hopkins University who co-led the study, although the idea to develop it came from our own work. "It can essentially solve partial differential equations on multiple geometries in any problem, in any field of science or engineering, such as in crash testing, orthopedics research, or other complex problems where shapes, forces, and materials change."
Trayanova's team evaluated the new AI on more than 1,000 cardiac "digital twins," which are extremely precise computer models of actual patients' hearts, in addition to showcasing DIMON's suitability for resolving other engineering issues. The platform achieved great prognosis accuracy by predicting the propagation of electrical signals through each distinct heart shape.
In order to investigate cardiac arrhythmia—an electrical impulse disturbance in the heart that results in irregular beating—Trayanova's team employs partial differential equations. Researchers can determine whether patients are at risk of developing the frequently fatal illness and provide treatment options using their cardiac digital twins.
Trayanova, who leads the Johns Hopkins Alliance for Cardiovascular Diagnostic and Treatment Innovation, stated, "We're bringing novel technology into the clinic, but a lot of our solutions are so slow that it takes us about a week from when we scan a patient's heart and solve the partial differential equations to predict if the patient is at high risk for sudden cardiac death and what is the best treatment plan." The speed at which we can find a solution with this new AI method is astounding. By using a desktop computer instead of a supercomputer, the time required to compute the prediction of a heart digital twin will drop from many hours to 30 seconds, enabling us to make it a component of the regular clinical process.
In order to solve partial differential equations, complicated objects, such as body organs or airplane wings, are typically divided into grids or meshes composed of tiny components. Each simple piece's difficulty is then resolved and reassembled. However, the grids must be updated and the solutions computed if their shapes change, as in crashes or deformations, which can be costly and computationally slow.
This issue is resolved by DIMON, which uses AI to comprehend the behavior of physical systems in a variety of shapes without requiring a complete recalculation for every new shape. The AI is far quicker and more effective at activities like designing or modeling shape-specific scenarios because it uses learned patterns to forecast how variables like heat, stress, or motion will react rather than breaking forms into grids and repeatedly calculating equations.
The group is adding cardiac pathology that causes arrhythmia to the DIMON framework. According to Minglang Yin, a Johns Hopkins Biomedical Engineering Postdoctoral Fellow who created the platform, the technology's adaptability allows it to be used for shape optimization and numerous other engineering activities where solving partial differential equations on novel shapes is frequently required.
"DIMON maps the solution to several new shapes after first solving the partial differential equations on a single shape for each problem. Its amazing adaptability is highlighted by its shape-shifting capacity, according to Yin. "We are eager to use it to solve a variety of issues and to make it available to the larger community so they can expedite their engineering design solutions."
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Revolutionary Thermal Switches Increase Energy Efficiency
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Posted by Okachinepa on 01/04/2025 @
Courtesy of SynEvol
Credit: Hokkaido University
Modern thermal management systems depend on thermal switches, which are electrically powered devices that regulate heat transport. However, due to their poor performance, conventional electrochemical thermal switches have not been widely used in industries including waste heat recovery, electronics, and energy generation.
A ground-breaking approach has been presented by a research team headed by Professor Hiromichi Ohta of Hokkaido University's Research Institute for Electronic Science. They created a very effective and environmentally friendly substitute by using cerium oxide (CeO2) thin films as the active component in thermal switches. Their ground-breaking research was just released in Science Advances.
Courtesy of SynEvol
Credit: Hokkaido University
The study team demonstrated that CeO2-based thermal switches can outperform previous standards. "The innovative device sets a new standard for electrochemical thermal switches with an on/off thermal conductivity ratio of 5.8 and a thermal conductivity (κ)-switching width of 10.3 W/m·K," says Ohta.
In its minimum state (off-state), the thermal conductivity is 2.2 W/m·K; however, in its oxidized form (on-state), it dramatically increases to 12.5 W/m·K. These performance measurements show exceptional durability and dependability for prolonged use in real-world applications, remaining constant after 100 cycles of reduction and oxidation.
Courtesy of SynEvol
Credit: Hokkaido University
Utilizing cerium oxide, a material that is abundant in the earth and known for its ecological sustainability and economic feasibility, is a noteworthy advantage of this technology. CeO2 provides a sustainable and easily accessible substitute for traditional thermal switches, which rely on expensive and limited resources. This lowers costs and the environmental impact of thermal management systems. As a result, the technique is more effective, scalable, and applicable to a wider range of industrial sectors.
An important advancement in thermal management technology has been made with the creation of CeO2-based thermal switches, which have a wide range of uses in sectors including electronics cooling and renewable energy systems. These switches effectively control infrared heat flow, improve waste heat recovery, and support energy-efficient systems. They are used in thermal shutters and sophisticated displays.
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Princeton Researchers Create Amazing New Substance
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Posted by Okachinepa on 01/01/2025 @
Courtesy of SynEvol
Credit: Princeton University
Engineers at Princeton have created a scalable 3D printing method that allows them to create soft polymers with tunable stretchiness and flexibility, as well as being economical and recyclable—a combination of properties that are rarely found in materials that are sold commercially.
A team lead by Emily Davidson described how they produced 3D-printed objects with adjustable stiffness using thermoplastic elastomers, a type of commonly accessible polymers, in a research published in Advanced Functional Materials. The developers were able to program the physical characteristics of the plastic by creating the print path for the 3D printer. This allowed the gadgets to flex and stretch in one direction while staying stiff in another.
The potential uses of this approach in areas like soft robotics, medical devices, prostheses, lightweight helmets, and customized high-performance shoe soles were emphasized by Davidson, an assistant professor of chemical and biological engineering.
The smallest level of the material's interior structure is crucial to its performance. The study team employed a block copolymer type that, within a stretchy polymer matrix, generates stiff cylindrical structures that are 5-7 nanometers thick (human hair is roughly 90,000 nanometers thick). These tiny cylinders were oriented by the researchers via 3D printing, resulting in a 3D printed material that is soft and elastic in almost every direction yet hard in one. These cylinders can be oriented in many orientations within a single object by designers, creating soft constructions that show stretchiness and rigidity in different areas.
"We are able to control the nanostructures that the elastomer we are using forms," Davidson stated. This gives designers a lot of influence over the final goods. "We are able to design materials with specific properties in various directions."
Selecting the appropriate polymer was the first stage in creating this procedure. The block copolymer that the researchers selected is a thermoplastic elastomer, which hardens into an elastic substance when cooled but can be heated and treated as a polymer melt. Polymers are extended chains of interconnected molecules at the molecular level. Block copolymers are composed of many homopolymers joined to one another, while traditional homopolymers are lengthy chains of a single repeating monomer. These distinct areas of a block copolymer chain resemble water and oil Rather than combining, they separate. This characteristic was employed by the researchers to create a material with stiff cylinders inside a flexible matrix.
The researchers created a 3D printing method that successfully induces the alignment of these stiff nanostructures by applying their understanding of how these block copolymer nanostructures originate and react to flow. The researchers examined how the physical characteristics of the printed material may be regulated by printing rate and controlled under-extrusion.
The lead author of the paper, Alice Fergerson, a Princeton graduate student, discussed the method and the crucial part thermal annealing—the regulated heating and cooling of a material—plays.
"I think one of the coolest things about this technique is the many functions that thermal annealing performs—it not only significantly enhances the properties after printing, but it also makes the items we print reusable and even capable of self-healing in the event that they break or get damaged."
One of the project's objectives, according to Davidson, was to develop soft materials with regionally adjustable mechanical qualities in a way that is both economical and scalable for industry. Materials like liquid crystal elastomers can be used to produce comparable structures with regionally controlled characteristics. However, according to Davidson, those materials are costly (up to $2.50 per gram) and necessitate a multi-step manufacturing procedure that includes meticulously regulated extrusion and UV light exposure. Davidson's lab uses thermoplastic elastomers that can be manufactured using a commercial 3D printer and cost around one cent per gram.
The researchers have demonstrated that their method can add useful additives to thermoplastic elastomers without compromising material property control. In one instance, they introduced an organic compound created by the group of Professor Lynn Loo that causes the plastic to glow red when exposed to UV radiation. They also showed off the printer's capacity to create intricate, multi-layered structures, such as a little plastic vase and printed lettering that spelled out PRINCETON using sharp turns.
By improving the internal nanostructures' order and perfection, annealing is essential to their process. According to Davidson, annealing also makes the material's self-healing qualities possible. The researchers can anneal a flexible piece of the printed plastic to reattach it after cutting it as part of the projectthe substance. The material that was restored showed the same traits as the original sample. The original and the restored material showed "no significant differences," according to the researchers.
In the future, the study team anticipates investigating novel 3D printable designs that will work with wearable electronics and biomedical devices, among other uses.
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