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Flow Sensor Based on Coulometric Interrogation of a Graphene Microelectrode
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Published: 3/1/2024   |   Inventor(s): Jinglei Ping, Xiaoyu Zhang
Category(s): Devices & sensors, Engineering, Healthcare, Life Sciences, Research tools, Electronics
CAPACITIVE ARTIFICIAL NEURAL NETWORKS
                                            
Published: 6/26/2023   |   Inventor(s): Jianhua (joshua) Yang, Qiangfei Xia, Mark McLean, Zhongrui Wang, Qing Wu
Category(s): Computers, Electronics, Engineering, Communications & internet
ARTIFICIAL NEURONS USING DIFFUSIVE MEMRISTOR
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Published: 6/26/2023   |   Inventor(s): Jianhua (joshua) Yang, Qiangfei Xia, Mark McLean, Qing Wu
Category(s): Devices, Computers, Communications & internet, Devices & sensors, Electronics, Engineering, Nanotechnology
Thermoelectric Facades
Buildings consume 40% of energy in the United States, and influence greenhouse gas emissions. Given the high energy usage and inefficiencies found in conventional HVAC systems, new heating and cooling sources are needed to reduce buildings’ carbon footprint. Moreover, integration of different building systems, particularly building envelope and HVAC, are essential for high-performance buildings.

 

Here, the inventors have conceived and demonstrated the thermoelectric facade, a novel facade system that integrates active and conventional thermoelectric (TE) modules for cooling, heating and energy generation. TE modules generate heat or cooling when electricity is applied, exploiting the Peltier effect, and produce a voltage when exposed to a temperature gradient, utilizing the Seebeck effect. Coupled with heat sinks, conductive materials and an electronic controller, the TE modules are employed in the facade system to heat or cool interior spaces of buildings, providing highly efficient and localized thermal management without requiring ducting, piping, or other large installations commonly associated with forced-air systems. In addition, thermoelectric facades can take advantage of temperature differences between interior and exterior to generate electricity at those times when active heating or cooling is not in use.

 

This novel, intelligent facade system can be integrated into various facade types, regardless of the building function. Its modularity allows for easy installation into façade assemblies of the existing buildings, increasing the overall energy performance of the building. Additionally, they can be used in the design and construction of new buildings with various types of building envelope, including curtain walls, rainscreen facades with aluminum cladding, opaque facades with window and vertical shading, and/or opaque facades with window and horizontal shading.

Published: 6/26/2023   |   Inventor(s): Ajla Aksamija, Zlatan Aksamija
Category(s): Clean Energy, Devices, Engineering, Electronics
Phyjama: Physiological Sensing via Fiber-enhanced Pyjamas
While there are many smart textile-based garments on the market that perform continuous cardiac and respiratory monitoring, they generally use flexible electronic components that are integrated with the textiles. Such clothing tends to be form-fitting and thus uncomfortable to be able to get a good physiological signal. Additionally, the garments aren’t robust, as they’re difficult to wash and the electronic components are damaged over time.

 

This invention, by Professors Trisha Andrew and Deepak Ganesan, enables physiological sensing with loose clothing. Smart garments incorporates two types of all-textile pressure sensors: a triboelectric sensor based on the contact between two oppositely charged fabrics, and a first-of-its-kind all-textile static pressure sensor. The triboelectric sensor is used for sensing dynamic pressure, and the static pressure measures pressure between the body and a surface, such as a bed, chair, or arms resting at a person’s side. The signals from these two types of sensors, which are connected to the electronics via conductive threads, are processed through a novel signal processing pipeline that can fit in a clothing button. Measurables include posture, respiration, heartbeat, gait, sway, and balance.

 

Applications for these garments are wide ranging, including sleep sensing, health monitoring, and next-generation virtual reality (VR).

Published: 11/15/2023   |   Inventor(s): Deepak Ganesan, Trisha Andrew, Seyedeh Zohreh Homayounfar, Ali Kiaghadi, Jeremy Gummeson
Category(s): Devices & sensors, Engineering, Electronics
High-Yield High-Quality Graphene by exfoliation of graphite
Graphene sheets are prized for their unusual but exciting properties, including extremely high mechanical strength and ability to efficiently conduct heat and electricity. These properties open up a myriad of applications in medicine, electronics, energy, and sensors. However, the production of graphene, which is derived from the exfoliation of graphite, is currently challenged by low efficiency and long exfoliation times.

This invention uniquely combines two techniques, flow and sonication, to overcome these challenges. A graphite suspension is first subjected to a flow process, where it is mixed with zirconium oxide pebbles. Collisions between the graphite and the pebbles modify the graphite’s surface, making it easier for the solvent molecules to “wedge” in between layers during subsequent sonication, significantly increasing graphene exfoliation time-efficiency.

Published: 6/26/2023   |   Inventor(s): H. Winter, Christos Dimitrakopoulos
Category(s): Engineering, Electronics, Devices & sensors, Clean Energy
Hierarchically Ordered Nanoscale Electric Field Concentrators for Embedded Thin Film Devices
Resistance switching devices, also known as memristive devices, represent the next generation in computing. With a typical metal-oxide-metal structure, memristors change resistance under different external biases and retain this new resistance even when power is turned off. This allows memristors to store data without needing constant power like in traditional computer memory. Memristors have other desirable properties such as low power consumption, fast switching speed, and multistate logic potential. These properties open up next generation computing applications in non-volatile memory, reconfigurable switches, bio-inspired neuromorphic computing, and radiofrequency switches. However, before these applications are enabled, significant technical challenges in memristors must be overcome. These include cycle-to-cycle instabilities in operating voltage and resistance states, which cause memory retention and device endurance issues.

 

Professor Stephen Nonnenmann and his laboratory address these instability issues by embedding highly ordered metal nanoislands in the memristor’s oxide switching layer. Through a unique template-directed nanoisland embedding procedure, the nanoisland diameter, spacing, and area density can be precisely controlled. The Nonnenmann lab found that through precise control of these variables, the growth of conductive filaments formed through the memristor’s oxide layer, which enable its unique properties, can be more precisely controlled, leading to a nearly 100% improvement in uniformity performance in one device case.

Published: 6/26/2023   |   Inventor(s): Stephen Nonnenmann, Jiaying Wang
Category(s): Computers, Electronics, Engineering, Nanotechnology, Material science, Devices & sensors
Neuromorphic Computing Memristive Device
Resistance switching devices, also known as memristive devices, represent the next generation in computing. With a typical metal/insulator/metal structure, memristors change resistance based on past current flow and retain this new resistance even when turned off. This allows memristors to store data without needing constant power like in traditional computer memory. Memristors have other desirable properties such as low power consumption, fast switching speed, and great cycling ability. These properties open up next generation computing applications in non-volatile memory, reconfigurable switches, bio-inspired neuromorphic computing, and radiofrequency switches.

 

Here, Dr. Qiangfei Xia and Dr. Joshua Yang have invented a Ta/HfO2/Pt memristive device that can be used for multilevel memory and for neuromorphic computing. The device exhibits bipolar resistive switching with low programming voltage (~1.5 V), high endurance (100 billion cycles), and long data retention time (37,000 years at 85 C). The device can be programmed to multiple resistance states with long retention time for each individual state. Finally, spike dependent plasticity (STDP) is also demonstrated for this device. The device also has the advantage of being able to be fabricated using traditional CMOS materials and techniques.

Published: 6/26/2023   |   Inventor(s): Qiangfei Xia, Hao Jiang, Jianhua Yang
Category(s): Devices, Electronics
Low Cross-Polarization Decade-Bandwidth Ultra-Wideband Antenna Element + Array
Electronically scanned arrays with ultra-wideband (ESA-UWBs) performance are desirable for applications such as multi-functional systems, high-throughput or low-power communications, high-resolution and clutter resilient radar/sensing, and electromagnetic warfare systems. For these applications, Vivaldi arrays are popular for their excellent impedance performance, but do suffer from unintended polarization, which leads to loss of service or reduction of throughput. To correct for these problems, one can add additional feeding circuitry; however, that will add to complexity and cost and reduce bandwidth capability.

This invention improves upon prior art Vivaldi designs, creating an antenna that has: (1) large instantaneous bandwidths; (2) excellent impedance matching; (3) good polarization isolation. Dr. Vouvakis' antenna is also easier to manufacture because the body is made up of smaller disconnected components that are easier to solder and notch than a single long flair Vivaldi of the prior art. Finally, because the design is based on Vivaldi, this antenna invention will be backwards compatible with legacy wideband phased array platforms.

Published: 6/26/2023   |   Inventor(s): Marinos Vouvakis, John Logan, Rickie Kindt
Category(s): Communications & internet, Electronics, Engineering
WearID: RFID Wristband Reader
Advances in RFID technology are opening up a myriad of commercial applications related to identifying and interacting with objects, from home automation and health and wellness to augmented reality and tele-rehabilitation. Passive UHF RFID readers are a particularly attractive option due to their low cost and no maintenance; however, their limited range necessitates the use of many readers to cover a single large room, an expensive and labor-intensive process.

This invention, known as WearID, overcomes the traditional limitations of UHF RFID readers through end-to-end design innovation, optimizing the wearable reader for low power, form-factor, and performance. WearID is able to detect grasping, releasing, touching, and passing near tagged objects.

Published: 6/26/2023   |   Inventor(s): Deepak Ganesan, Pan Hu, Jeremy Gummeson, Ali Kiaghadi
Category(s): Devices & sensors, Communications & internet, Electronics, Engineering, Software & information technology, Healthcare
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