Asynchronous circuits have many advantages over their synchronous counterparts in terms of robustness to parameter variations, wide supply voltage ranges, and potentially low power by not needing a clock, yet their promise has not been translated yet into commercial success due to several issues related to design methodologies and the need for handshake signals. Stochastic computing is another processing paradigm that has shown promises of low power and extremely compact circuits but has yet to become a commercial success mainly because of the need for a fast clock to generate the random streams. The recently proposed Asynchronous Stream Processing combines the best features of asynchronous circuits (lack of clock, robustness) with the best features of stochastic computing (processing on streams) to enable extremely compact and low power sensing “motes” that can finally fulfill the promise of smart dust, another concept that was ahead of its time and yet to achieve widespread deployment. This seminar will go into the details of an Asynchronous Stream Processing (ASP) mote. The ASP mote includes input sensors, asynchronous sigma-delta modulators that convert the sensor data into streams, asynchronous stream processing units to process the streams, analog memories to store data, energy sources, and pulse-based ultra-wide band (UWB) units to transmit the processed data. Among the unique characteristics of the ASP mote are: exact stream adders based on Sigma-Delta modulation, and the direct transmission of conditioned Sigma-Delta streams as pulses for UWB.

Polymer electrolyte membrane (PEM) fuel cells are electrochemical devices that directly convert the chemical energy stored in fuel into electrical energy with a practical conversion efficiency as high as 65%. They are widely regarded as a promising power source for portable, transportation and stationary applications. Though several fuel cell electric vehicles (FCEV) such as Toyota Mirai and Hyundai Nexo were successfully commercialized in recent years, technological advancements are still highly needed to further improve fuel cell performance (e.g. efficiency and durability) and to reduce cost. In this talk, I will present the status of PEM fuel cell development and discuss multiphysics and data-driven modeling approaches for PEM fuel cell design that has been actively developed at the UC Irvine. Some fundamental and material aspects critical to fuel cell development will be discussed. Examples of material design and operational condition using physical models, machine learning, and genetic algorithms (GA) will be presented and explained in detail.

The senses do not work in isolation in the real world. What we see, hear and feel in the environment are often combined, and this sensory integration helps us carry out daily activities like recognising other people or understanding what they say in a noisy environment. I will present behavioural and brain data showing different neural mechanisms for sensory integration. I will then present recent work to show how sensory integration (e.g. between vision and touch, or between hearing and touch) can improve performance in different tasks and help to reduce subjective pain experiences. These examples highlight the importance of understanding the mechanisms underlying sensory integration.

A nanostructure of graphene oxide (GO) and carbon nanotubes (CNTs) decorated with silver nanoparticles (AgGNT) has been prepared via a molecular-level-mixing (MLM) method followed by a subsequent freeze-drying and reduction process. The obtained well-dispersed AgGNT nanostructures were then applied as fillers to reinforce the poly(ether ether ketone) (PEEK) matrix. Owing to the unique morphology of AgGNT nanostructures, which made them uniformly dispersed in the PEEK matrix and formed a 3D network structure, the AgGNT-PEEK composites displayed much higher thermal conductivity and around 109 times better electrical conduction performance than pure PEEK, and superior thermal durability even above the melting temperature of pure PEEK. Thus, the AgGNT-PEEK composites have shown great potential for applications such as semiconductors, high-temperature electrical applications, aerospace, and automobile materials.

The Bitcoin cryptocurrency keeps cropping up in the news. Cryptocurrencies are based on blockchain, a digital, public distributed ledger. The main motivation for cryptocurrencies relates to uncertainties related to intermediaries. Many are now advocating using blockchain as a universal solution for transactions, whether it is goods, services, or information that needs to be transferred or exchanged. Unfortunately, it’s not that simple. Some people compare blockchains to giant spreadsheets, where all transactions between given parties are registered and approved. Every time a new transaction is performed, it is added to the blockchain – and also copied to all users. The result is a solution that is independent of intermediaries – all the blockchain participants have the same information at a given time, which enables making the majority to adjudicate any disagreements. Running a blockchain is not free, however, and there are some strict requirements on the operations the users must perform. This contributes to making blockchains unsuited to fulfilling some of the expectations they are met with. In this talk, we will briefly cover the basics of what a blockchain is, and then go on to describe five application areas where blockchain probably cannot provide a good solution.

Critical infrastructure is a key area in cybersecurity. In the U.S., it was front and center in 1997 with the report from the President’s Commission on Critical Infrastructure Protection, and now affects countries worldwide. Although there is more awareness of cybersecurity now, the threats have also evolved in the interim period. Critical Infrastructure Protection must address all types of cybersecurity threats - insider threat, ransomware, Supply Chain Risk Management issues, and so on. We then discuss the challenge and the potential solutions for the integration of secure supply chain risk management into development projects. Development projects are typically focused on the development of software artifacts. As a result, development does not always include methods to ensure that code in commercial off-the-shelf (COTS), open source, and reused software products cannot be compromised. In this talk, we discuss the threats and actual attacks, and mitigation methods.

Critical infrastructure is a key area in cybersecurity. In the U.S., it was front and center in 1997 with the report from the President’s Commission on Critical Infrastructure Protection, and now affects countries worldwide. Although there is more awareness of cybersecurity now, the threats have also evolved in the interim period. Critical Infrastructure Protection must address all types of cybersecurity threats - insider threat, ransomware, Supply Chain Risk Management issues, and so on. We then discuss the challenge and the potential solutions for the integration of secure supply chain risk management into development projects. Development projects are typically focused on the development of software artifacts. As a result, development does not always include methods to ensure that code in commercial off-the-shelf (COTS), open source, and reused software products cannot be compromised. In this talk, we discuss the threats and actual attacks, and mitigation methods.