Inno Wing TechTalks

About the Inno Wing TechTalk
TechTalk is a series of forums and dialogues given by engineering researchers of diverse academic backgrounds to share their insights on innovation-related topics.
HKAES TechTalks

HKAES TechTalk – Metallurgical Issues in Water Supplies in Hong Kong

June 26 2024 (Wednesday) 4:00-5:00pm
Water supply in Hong Kong began more than 170 years ago in 1851. Initially, only fresh water was supplied but serious droughts in the 1950s-60s led to the development of one of the world’s first SWFT – “seawater for toilet flushing” systems, which continues today and covers around 85% of the Hong Kong population. This talk will focus on the metallurgical issues encountered in the supply of both fresh and sea water in Hong Kong. For fresh water, excess lead (Pb) was reported in a newly completed housing estate in 2015 and since then, measures have been taken to tighten the control of materials used in pipes and solder joints. Yet, potable-water grade copper-alloy materials allowable by international standards are still not entirely Pb-free, and this talk will report a scientific study on the metallurgical pathways for Pb-leading from such materials. For seawater supply, using the SWTF system for more than 60 years is met with increasingly frequent pipe bursts due to seawater-induced corrosion of the ferrous pipe materials. This talk will report an on-going study on a type of corrosion inhibitors which, if added to the seawater, can potentially lengthen the lifespan of the pipes. The research reported here is supported by the Research Impact Fund of the Hong Kong Research Grants Council and the Water Supplies Department of the HKSAR Government.

HKAES TechTalk – Integration of AI and Wireless Networks for 6G Systems

May 21 2024 (Tuesday) 4:00-5:00pm
AI will be tightly integrated with wireless networks in future 6G wireless systems. On one hand, more and more AI applications will be running directly on mobile terminals for inferencing and training because dataset exists locally at mobile or IoT devices but large neural network models will be in the cloud. As such, wireless communication networks will be “in-the-loop” between mobile devices and the neural network models. it is important for future wireless networks to be optimised to support more efficient AI deployment. On the other hand, AI as a powerful tool can have huge potential to solve challenging problems in wireless communications design, resulting in better and more efficient wireless networks. There are lots of potential to deploy domain-specific AI design to implement challenging modules such as the physical layer and system designs in wireless systems. In this talk, we shall explore the integration of AI and future 6G wireless networks.

HKAES TechTalk – Creating New Radio Frequency Wave Technology for 6G

April 23 2024 (Tuesday) 4:00-5:00pm
Radio frequency (RF) waves are a fundamental phenomenon that can carry electromagnetic signals and energy through space and interact with it. Their use in wireless communication has revolutionized our lives and created a mobile information society and new industries. However, RF wave technology can do much more and in this talk I explore new RF wave technologies that can be further exploited for 6G. I broadly classify the new RF technologies into wave shaping and wave sensing and in this talk I focus on the development of RF Imaging, RF energy harvesting and reconfigurable intelligent surfaces (RIS). In particular both the concepts and experimental results obtained from our prototypes are presented for each of these technologies. Furthermore, while each of these technologies is promising, significant further research is needed to exploit the enormous potential of new RF wave technology for 6G and this is also detailed.

HKAES TechTalk – Collaborative Edge Computing for Ubiquitous AI

March 26 2024 (Tuesday) 4:00-5:00pm
Edge computing provides a powerful way to rapidly analyze data and process tasks at the edge of the network, closer to the end-user. Edge AI extends edge computing to enable AI on edge devices to make instantaneous intelligent decisions. In this talk, I will describe the vision of future Edge AI, called Ubiquitous AI, empowered by collaborative edge computing (CEC), which is a new-generation scalable edge computing infrastructure. With the computing power shared by collaborative edge nodes, edge AI models can be trained and seamlessly deployed jointly by the edge nodes that can be geographically distributed across a wide area. I will highlight the architecture and framework of CEC and how it enables ubiquitous AI demanded by advanced smart city applications like autonomous driving, industry 4.0 and metaverse.

HKAES TechTalk – How clean is the air we breathe in urban areas?

February 20 2024 (Tuesday) 4:00-5:00pm
Air pollution continues to cause significant environmental health risks, leading to numerous premature deaths worldwide each year. To protect public health, many governments have implemented regulatory policies on mass concentration of major air pollutants, referencing the guideline values recommended by the World Health Organization (WHO). However, new scientific evidence suggests various components in the air have different health effects. This talk will share research findings on the key toxic components of urban air from both chemical and biological aspects and their associated emission sources responsible for health effects.

HKAES TechTalk – Living with Climate Extremes – Hong Kong Perspective

January 23 2024 (Tuesday) 4:00-5:00pm
Hong Kong has a sub-tropical climate and wide variety of weather. Different extreme weather events, including tropical cyclone, heavy rain, and extreme temperatures, can affect Hong Kong and result in significant impacts to the society. Looking into the future, against the background of climate change and local urbanization, Hong Kong will expect even warmer climate, more variable rainfall, more intense typhoons, and a sea level that keeps rising in the coming centuries. This may affect the frequency and severity of various extreme weather and increase the risk of related weather hazards. This presentation will review different kinds of high impact extreme weather in Hong Kong and their past trend and future projection. Moreover, a brief overview on the concept of climate risk management will be shared.

HKAES TechTalk – Hong Kong’s Climate Action Plan 2050

The Hong Kong Government issued the “Climate Action Plan 2050” in October 2021. This blueprint sets out four decarbonisation strategies : (1) net-zero electricity generation; (2) energy saving and green buildings; (3) green transport and (4) waste reduction. The plan provided a clear timeline to reduce total carbon emissions by half before 2035 from the 2005 level and to achieve carbon neutrality before 2050.

HKAES TechTalk – Magneto-electric Dipole – Advanced Antenna Technology for a Smart World

Since Heinrich Hertz developed the first antenna in 1887 to demonstrate the existence of radio waves, the antenna has become the linchpin in countless wireless systems and devices. With the increasing demand for faster wireless connectivity, rising adoption of smartphones for consumer electronics, and accelerating digitization, stringent requirements, such as wide bandwidth and compact size, are imposed on antenna technology. The magneto-electric (ME) dipole is proposed to tackle the new challenges. It has been developed for mobile communications, global navigation receivers, radars, sensors, medical imaging systems and wireless power transfer systems. Compared with conventional antennas such as dipoles, slots and microstrip antennas, the ME dipoles have many distinguished features including wide bandwidth, low cross-polarization, low back radiation and stable gain and beamwidth over the operating frequencies. An overview of the theory and applications of the ME dipoles will be presented.

HKAES TechTalk – Fluid Mechanics for Carbon Reduction in Wastewater Treatment Plants –

November 2 2023 (Thursday) 4-5pm
The Hong Kong Harbour Area Treatment Scheme (HATS) serves a population of over 5 million. It ensures protection of the Tsuen Wan beaches and good water quality in Victoria Harbour. In the Stonecutters Island treatment works, 300 tonnes of 10 percent sodium hypochlorite solution (6 L/s) are dosed into a river of sewage (1.8 million m3/d) every day. In actual operation it is found that most of the chlorine is actually consumed without being used for disinfection. This talk presents an engineering innovation on how to mix the small chlorine dose with the large sewage flow, resulting in up to 30 percent reduction of chlorine demand – with significant savings of chemicals and reduction of carbon footprint of 1170 tonnes/year. The technology is generally applicable to chlorine disinfection of primary effluent in many developing countries.

TechTalks
Young Scholar TechTalks

Young Scholar TechTalk – Empowering Pervasive Healthcare: Mobile Analytics Systems Leveraging Multimodal Data

June 11 2024 (Tuesday) 4:30-5:30pm
Pervasive healthcare, also sometimes referred to as ubiquitous healthcare, is a research field that focuses on developing healthcare solutions that are seamlessly integrated into everyday life, making healthcare services available anytime and anywhere. It merges concepts from pervasive computing with health and wellness care to create solutions that are woven into the daily routines of individuals. In light of the increasing availability of diverse data sources, such as user-environment contexts and ambient sensor signals, this talk will explore the new challenges and opportunities in developing mobile analytics systems to empower pervasive healthcare. We will begin by introducing these challenges and opportunities, followed by presenting two mobile analytics systems designed for personal and public health. These systems illustrate how mobile analytics can enhance pervasive healthcare. Finally, we will discuss future directions for integrating mobile analytics into the pervasive healthcare landscape.

Young Scholar TechTalk – On Causality and the Upper Limit of Sound Absorption

April 30 2024 (Tuesday) 4:30-5:30pm
Sound absorption across a wide range of frequencies is a focus in contemporary acoustics. Recently, integral bounds of absorption or reflection coefficients were introduced as a guide of design optimization following the footsteps of electromagnetics, where integral relations were derived based on system causality considerations. This talk carefully examines the proper formulation of physical causality and its implications on the scattering properties of the system. Taking into consideration the effects of different physical boundary conditions and the bulk absorber material, a more generalized integral bound is derived. It becomes evident that, while the bound exists, it is governed by system stiffness rather than the causality constraint. By studying the effects of various approximations made during mathematical derivations, the physics of the bound is thoroughly discussed, and the limitations in utilizing integral bounds as reference for design optimization are highlighted. The findings are expected to have significant implications for the development of effective noise reduction strategies and the advancement of smart acoustic design.

Young Scholar TechTalk – Customizable Acoustic Metamaterials on Frequency and Spatial Dimensions

March 12 2024 (Tuesday) 4:30-5:30pm
Acoustic metamaterials are artificially designed structured ‘atoms’. Initially, scientists discovered that these meta-atoms can exhibit extraordinary properties beyond those found in natural materials, such as negative density and negative modulus, through localized resonance, which sparked significant interest in the academic community. Subsequently, it was confirmed that these unique narrow-band frequency responses can be extended to broadband impedance designs, leading directly to the emergence of absorption metamaterials and opening up large-scale applications in noise reduction. In recent years, the potential of customizable metamaterials has gradually been realized. We will present our latest works from two complementary perspectives: customized frequencies and spatial non-uniformity, which may open up new applications such as directional emission, stealth cloaking and automotive acoustics.

Young Scholar TechTalk – GRAINS: Proximity Sensing of Objects in Granular Materials

October 17, 2023 (Tuesday) 4:30-5:30pm
Proximity sensing is a method of detecting the presence of objects without making physical contact. However, this concept has not been widely explored in the context of granular materials, which are materials composed of small particles like sand or gravel. This is because granular materials have complex properties and the sensing needs to work without the aid of vision. In this presentation, I will introduce a system called GRAINS (Granular Material-Embedded Autonomous Proximity Sensing). GRAINS is designed to sense objects buried within granular materials by utilizing fundamental principles related to the behavior of granules, such as how they flow like a fluid, how they can become jammed. GRAINS uses force signals to determine the proximity of buried objects. It achieves this by analyzing force anomalies that occur when granules become jammed due to their proximity to objects. These force anomalies are learned in real-time by the system using a mathematical technique called Gaussian process regression. To capture these patterns, a probe is moved along a spiral trajectory within the granular material. The results of our experiments demonstrate that GRAINS can adaptively adjust its parameters to effectively work with different types of granules. It can perceive objects in the nearby vicinity, approximately 0.5 to 7 cm ahead, without the need for direct contact with the buried obstacles.
(project page: https://sites.google.com/view/grains2/home)

Young Scholar TechTalk – Secure and High-performance AI Serving: Protecting AI Secretes, Accelerating AI Insights

September 19, 2023 (Tuesday) 4:30-5:30pm
Driven by the remarkable success of artificial intelligence (AI) and edge computing, the deployment of well-trained private AI models on third-party edge devices for mission-critical applications has become increasingly prevalent. Safeguarding these private models on untrusted devices, while simultaneously speeding up model serving (i.e., inference) through accelerators like GPUs, has escalated in urgency.
We introduce SOTER, a new AI serving system that, for the first time, achieves both high security and high performance. Harnessing the associativity property of AI operators, SOTER presents an innovative approach—transforming computationally expensive AI operators into parameter-morphed equivalents for secure execution on untrusted but fast GPUs, and losslessly restoring inference results within trusted execution environments (TEEs) in CPUs. Experimental results on six prevalent AI models in the three most popular categories show that, even with stronger model protection, SOTER achieves comparable performance with baselines while retaining the same high accuracy as insecure AI model inference.

Young Scholar TechTalk – Modeling Uncertainty of Connected Vehicle Penetration Rate: Theory and Application

September 12, 2023 (Tuesday) 4:30-5:30pm
The rapid development of communication technologies enables real-time information exchange between vehicles, thus being virtually connected. However, the full connected vehicle (CV) deployment will take a long time and may never be achievable, due to privacy, security, and willingness. Knowledge of the CV penetration rate is thus crucial for realizing numerous beneficial applications during the prolonged transition period. Although several novel models have been proposed for CV penetration rate estimation, they are solely point estimators. Direct use of these point estimators without considering their variability can lead to biased models or suboptimal solutions. To bridge this research gap, this study proposes a series of analytical models to accurately estimate the variability of CV penetration rate. Comprehensive VISSIM simulations, real-world applications, and a simple CV-based adaptive signal control scheme demonstrate the readiness of the models for use in real-world situations and the potential of the models to improve system optimizations.

Young Scholar TechTalk – Chip-scale Sensing: From Classical to Quantum Regime

Miniature optoelectronic sensors which have features of convenient, reliable, economic, ultra sensitive, and capable of real-time measurement are highly desirable nowadays. However, currently reported optical and electronic sensing devices are still hindered with complex optical components and bulky equipment. Hence, we hope to further minimize the volume of the sensing system and get rid of the dependence on complex, expensive and bulky sensing components. In particular, we demonstrate a micro-scale III-nitride chip that integrates a light emitter (LED) and a photodetector (PD) together, realizing the emission and detection of signals in a single miniature chip. Thus, we have applied the device into some classical sensing, such as pressure, salinity content and cell activities sensing. Additionally, we also conduct integration on the diamond based quantum sensing system, and demonstrate a compact chip architecture (sub ~mm3 volume) being capable of on-chip quantum sensing.

Young Scholar TechTalk – HOF2 – Interact with Device through Simple and Robust Hand-Over-Face Gesture

Mobile devices have been like an extended part of ourselves, but can we really operate a mobile device just as naturally as how we control our fingers or body? We present HOF2, a novel input modality that uses simple gestures over your face to interact with your device. Unlike other gesture-based modalities, HOF2 is highly robust and can avoid false triggering caused by many unconscious gestures like scratching or wiping, while is still easy, comfortable and natural to use. Moreover, HOF2 is highly available and can be implemented on any mobile phone/tablet/computer with a single camera and without remote servers. In this TechTalk, we will present a live demo on iOS/iPadOS demonstrating the performance of HOF2 scheme in practice and explore some real-life use cases such as virtual conferencing, selfie, or TV controller. We believe there are far more possibilities waiting to be explored with this novel interaction scheme.

Young Scholar TechTalk – High-throughput Cell Mechanics Characterization with Microfluidics

Cells can sense mechanical stimuli and convert them to biochemical signals for various specific cellular responses, such as stem cells differentiation, initiation of transcriptional programs, and cell migration. Cell mechanics focuses on the mechanical properties and behaviours of living cells and how cell mechanics relates to various cell functions. Currently, traditional cell mechanics measurement methods are cumbersome, low-throughput, and expensive to deploy. By exploiting microfluidic technology, Dr. Johnson Cui is investigating the cancer cell mechanics and developing an accurate, easy-to-use cell mechanics measurement platform for cell mechanics research and also for cancer diagnosis and therapeutics in the future.

Young Scholar TechTalk – Learning to Control and Coordinate Hybrid Traffic Through Robot Vehicles at Complex and Unsignalized Intersections

Intersections are essential road infrastructures for traffic in modern metropolises; however, they can also be the bottleneck of traffic flows due to traffic incidents or the absence of traffic coordination mechanisms such as traffic lights. Thus, various control and coordination mechanisms that are beyond traditional control methods have been proposed to improve the efficiency of intersection traffic. Amongst these methods, the control of foreseeable hybrid traffic that consists of human-driven vehicles (HVs) and robot vehicles (RVs) has recently emerged. We propose a decentralized reinforcement learning approach for the control and coordination of hybrid traffic at real-world, complex intersections–a topic that has not been previously explored. Comprehensive experiments are conducted to show the effectiveness of our approach. We show that using 5% RVs, we can prevent congestion formation inside the intersection under the actual traffic demand of 700 vehicles per hour. When there exist more than 50% RVs in traffic, our method starts to outperform traffic signals on the average waiting time of all vehicles at the intersection.

Young Scholar TechTalk – Blowing Bubbles in Membranes for More Efficient Freshwater Production

Global scarcity and contamination of freshwater pose a significant threat to sustainable development. To address this crisis, reverse osmosis (RO) technology has been playing a pivotal role in desalination and water reuse for freshwater production. The effectiveness of the RO membrane filtration is highly dependent on its surface functional rejection layer. My research focuses on shaping this rejection layer to be a voids-bearing structure, resembling blowing bubbles within the layer. This technique will result in a thinner rejection layer with a larger surface area, favoring water transport. On this basis, shaping branch bubbles to resemble a tree or coral can potentially achieve an exponential increase in water filtration efficiency, resulting in faster production of freshwater with significantly lower energy consumption.

Young Scholar TechTalk – Understanding Rainfall-induced Slope Failures from an Integrated Perspective

Climate change increases the frequency and intensity of extreme rainfall events and magnifies the threat of rainfall-induced slope failure. The consequences of these failures can be dramatic and devastating if flow slides are triggered. While considerable efforts have been made in the past decades to understand the failure mechanisms and develop techniques to mitigate the hazards, the complexity of interplays of various factors causes it to remain an area of uncertainty and difficulty in geotechnical engineering. This talk will briefly review and discuss the main factors affecting rainfall-induced slope failures from a perspective integrating the geotechnical, hydrological, and climatological aspects. The two deadly landslides in Sau Mau Ping, Hong Kong, in June 1972 and August 1976, which caused 165 casualties, are revisited. We raise an intriguing question that has long been overlooked: why were the slopes able to withstand the 1972 rainfall but failed in the 1976 rainfall event, given that the rainfall intensity of the latter event was only half of the former. We explore the roles of geological and hydrological settings and the rainfall characteristics to look into the causes and mechanisms of these failures. Implications of the new findings for practice will also be discussed.

Young Scholar TechTalk – Flexible Learning of Quantum States with Generative Query Neural Networks

Deep neural networks are a powerful tool for the characterization of quantum states. Existing networks are typically trained with experimental data gathered from the specific quantum state that needs to be characterized. In this talk, Mr. Yan Zhu, from Department of Computer Science, will introduce a model of network that can be trained with classically simulated data from a fiducial set of states and measurements, and can later be used to characterize quantum states that share structural similarities with the states in the fiducial set. With little guidance of quantum physics, the network builds its own data-driven representation of quantum states, and then uses it to predict the outcome statistics of quantum measurements that have not been performed yet. The state representation produced by the network can also be used for tasks beyond the prediction of outcome statistics, including clustering of quantum states and identification of different phases of matter.

Young Scholar TechTalk – Cyber-Physical Spare Parts Intralogistics System for Aviation MRO

Spare parts management is a vital supporting function in aviation Maintenance, Repair,and Overhaul (MRO). Spare parts intralogistics (SPI), the operational perspective of spare parts management, significantly affects performance of MRO activities. This study proposes Cyber-Physical Spare Parts Intralogistics System (CPSPIS) to address the synchronization problems associated with the SPI business process and SPI resources. The proposed system applies Internet-of-Things technologies and unified representations to provide resources and operations traceability and visibility. Further, CPSPIS contributes several services with self-X abilities for real-time synchronization throughout the SPI process. In addition, CPSPIS develops applications and visualization tools for real-time cooperation between execution and decision-making. Finally, this study conducts a real-life case study in one of the largest aviation MRO organizations in Hong Kong, and discusses the quantitative and qualitative improvements of CPSPIS.

Young Scholar TechTalk – Subgraph Federated Learning with Missing Neighbor Generation

In computer science, a graph is a network modeling objects and their unique interactions. The graph learning model is a specialized machine learning model that learns on graphs. Similar to traditional machine learning models, a well-performed graph learning model can capture the global data distribution with sufficient and unbiased training data. However, in a distributed subgraph system, most data owners only possess small amounts of the data (small subgraphs) in their local systems and can have unpredictable biases.
In this talk, the speaker will introduce this novel yet realistic setting – subgraph federated learning, which aims to let distributed data owners collaboratively train a powerful and generalized graph learning model without directly sharing their subgraphs. Towards this setting, two major techniques are proposed by the research team. (1) FedSage, which trains a GraphSage model based on FedAvg to integrate node features, link structures, and task labels on multiple local subgraphs; (2) FedSage+, which trains a missing neighbor generator along FedSage to deal with missing links across local subgraphs. Empirical results and theoretical analysis of proposed models respectively demonstrate the effectiveness and prove the generalization ability.

Tech Talk – Anti-Covid-19 stainless steel

Stainless steel (SS) is one of the most extensively used materials in many public areas and hygiene facilities but has no inherent antimicrobial properties. Additionally, the SARS-CoV-2 exhibits strong stability on regular SS surfaces, with viable viruses detected even after three days. Undoubtedly, this has created a high possibility of virus transmission among people using these areas and facilities. Here, this talk presents the inactivation of pathogen microbes (especially the SARS-CoV-2) on SS surface by tuning the chemical composition and microstructure of regular SS. It is discovered that Pathogen viruses like H1N1 and SARS-CoV-2 exhibit good stability on the surface of pure Ag and Cu-contained SS of low Cu content, but are rapidly inactivated on the surface of pure Cu and Cu-contained SS of high Cu content. Significantly, the developed anti-pathogen SS with 20 wt% Cu can distinctly reduce 99.75% and 99.99% of viable SARS-CoV-2 on its surface within 3 and 6 h, respectively. Lift buttons made of the present anti-pathogen SS are produced using mature powder metallurgy technique, demonstrating its potential applications in public areas and fighting the transmission of SARS-CoV-2 and other pathogens via surface touching.

Tech Talk – dPRO: A Generic Performance Diagnosis and Optimization Toolkit for Expediting Distributed DNN Training

Distributed training using multiple devices (i.e., GPU servers) has been widely adopted for learning DNN models over large datasets. However, the performance of large-scale distributed training tends to be far from linear speed-up in practice. Given the complexity of distributed systems, it is challenging to identify the root cause(s) of inefficiency and exercise effective performance optimizations when unexpected low training speed occurs. To date, there exists no software tool which diagnoses performance issues and helps expedite distributed DNN training, while the training can be run using different machine learning frameworks. This paper proposes dPRO, a toolkit that includes: (1) an efficient profiler that collects runtime traces of distributed DNN training across multiple frameworks, especially fine-grained communication traces, and constructs global data flow graphs including detailed communication operations for accurate replay; (2) an optimizer that effectively identifies performance bottlenecks and explores optimization strategies (from computation, communication and memory aspects) for training acceleration. We implement dPRO on multiple deep learning frameworks (PyTorch, TensorFlow, MXNet) and representative communication schemes (AllReduce and Parameter Server architecture). Extensive experiments show that dPRO predicts performance of distributed training in various settings with<5% errors in most cases and finds optimization strategies with up to87.1%speed-up over the baselines.

Tech Talk – Digital Twin-Enabled Synchronization System for Smart Precast Construction

Prefabricated construction is an emerging construction approach to produce prefabricated components in the off-site factory and transport them to the construction site for assembly, which provides enhanced quality, productivity, and sustainability. On-site assembly is an uncertain and complex stage in prefabrication projects, due to high variability of outside conditions, organization of multi-contractors, and geographic dispersion of activities. Information technology is adopted for the management of precast on-site assembly, such as Internet-of-Things (IoT), Cyber-Physical Internet (CPS), and cloud computing, which generate massive digital twins of construction resources and activities. This tech talk introduces a digital twin-enabled real-time synchronization system (DT-SYNC) with a robotic testbed demonstration for smart prefabricated on-site assembly. On-site resources are converted into Smart Construction Objects (SCOs) attaching with UWB and RFID devices to collect and integrate real-time nD data (e.g. identity, location, cost, and construction progress). Through smart mobile gateway, various on-site resources and activities could be real-timely interoperated with their corresponding digital twins. Cloud-based services are provided for real-time monitoring through high-fidelity virtual models, and robotic control with automatic navigations and alerts. Supported by the cyber-physical visibility and traceability provided by digital twins, a real-time synchronization model is designed to organize and coordinate operations and resources with simplicity and resilience, which guarantees that the appropriate resources are spatiotemporally allocated to the appropriate activities.

Tech Talk – Sensing and Data Processing for Human Balancing Evaluation

Balance ability is human’s basic physiological ability that ensures stable standing and walking. Falls are major threats to the health and independent living of the elderly. 10% of the falls in the elderly are associated with fractures, and some can lead to head injuries and deaths. A highly effective human balance sensor is invented, which can capture high-resolution dynamic pressure distribution under human feet. The variation of the pressure distribution can be used to solve the dynamics of human motion while standing on the balance sensor. The algorithms using artificial intelligence are developed to assess the risk of falling for elderly people to help them prevent falls. Furthermore, this sensor can be used to measure balance ability of athletes, such as weightlifting, golf and gymnastics. In medical diagnosis, balance ability tests can provide important information for diagnostics of neural disease. It can also be used to identify drunk driving.

Tech Talk – Short-range exposure during close contact and the environmental interaction

Debate and scientific inquiries regarding airborne transmission of respiratory infections such as COVID-19 and influenza continue. Exposure was investigated under a face-to-face scenario, where people experience the highest risk of respiratory infection. The short-range airborne route was found to dominate exposure during close contact. Based on the fact that most of the outbreaks occurred in indoor environments, we built the link between long-range airborne transmission and short-range airborne route. Results suggest that effective environmental prevention strategies for respiratory infections require appropriate increases in the ventilation rate while maintaining a sufficiently low occupancy.

Tech Talk – Cold-formed Stainless Steel Structures under Concentrated Bearing Loads

The application of stainless steel (SS) as an alternative construction material has been developing in the last decade. SS construction has an outstanding structural performance, excellent corrosion resistance, and long-term durability. Moreover, the SS construction has a relatively low maintenance cost with possibility of a longer occupancy period, and thus it promotes sustainability in the construction industry. In combination with the cold-forming technique during the fabrication process, SS structures offer additional strength and a faster construction speed. However, the available international design standards for cold-formed stainless steel (CFSS) structures have not been developed thoroughly, specifically on the strength prediction of a member under concentrated bearing loads, which causes a web crippling. Therefore, a series of laboratory testing and computational simulations were conducted in this research to evaluate the existing design standards. The reliability analysis shows that the available strength predictions in the design standards are not safely used even though they are conservative. This research proposes new strength predictions that are safe and conservative, and it can be used for an improvement of the design standards.

Tech Talk – Engineering of quantum nanodiamonds

Diamond, the most famed of all gemstones, is unique in many ways. However, beyond the sparkle, diamonds have many unique properties for copious applications. In particular, nanoscale diamond particles, generally known as nanodiamonds (NDs), have several outstanding material qualities, offering a wide range of potential for basic science and industrial applications. The practical applications of the quantum NDs are highly dependent on obtaining a well-defined surface through cleaning. Here, this talk will first present a simple, reliable, and reproducible purification method, namely, the salt-assisted air oxidation treatment, which enables scale-up manufacturing of clean NDs. At the same time, it is discovered that NDs could work as an effective agent against oral infections. These findings will significantly enhance the scope of these little gemstones in diverse scientific and industrial fields, particularly in demanding areas such as biomedical and quantum sensing.

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