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Postgraduate YPEC 2021

PG01-Development of Thin Thermal Ground Planes for Electronic Cooling

A novel thermal ground plane has been developed and experimental studies on thermal ground planes (TGPs) for thermal management have been carried out.

TGP used in this paper features a copper casing, circular micropillars, and oxidized nanostructure copper foam wick structure, with water as working fluid. By studying the effect on thermal performance by the number of layers of porous wick structure of TGP, surface modification for a nanostructure-owning property of the copper wick structure and topper casing of different wettability. It is found that TGP with double layers of nanostructured copper foam wick structure and hydrophilic casing shows the best thermal performance among all the tested samples. A novel finding is that a double-layer wick structure with the same thickness owns a better thermal performance than a single-layer or quadruple-layer. Nanostructured wick structure also shows significant improvement from this project. Hydrophilic topper casing is superior to superhydrophobic/ superhydrophilic/ hydrophilic topper casing in axial heat transfer of the TGP.

Thermal management helps improve reliability and prevent premature failure and solve the barrier of energy-intensive electronics. Through the use of environmental-friendly materials, TGP improves energy efficiency for a sustainable digital world.

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Postgraduate YPEC 2021

PG05-Organic e-fuel for Sustainable Green Vehicle Technology

Environmental concerns associated with fossil fuels have accelerated transformation of the global transportation system, from conventional vehicles to green vehicle technology. Different concepts of green vehicle technology have been proposed and developed. However, there is need to introduce new concepts or improve the existing concepts to facilitate development of safe, affordable, and high-performance green ‘electric’ vehicle. In this project an organic e-fuel is formulated, synthesized, and evaluated for application in green vehicle technology. Organic molecules are synthetically tuneable, allowing them to be tailored and modified to have a combination of all the required properties of a suitable e-fuel. The e-fuel is prepared from nature derived materials making it safe and environmental-friendly. Furthermore, the e-fuel is water soluble and employs a PH neutral aqueous supporting electrolyte that is non-flammable and non-corrosive. The unique e-fuel investigated in this study opens a novel pathway for designing and investigating organic molecules for application as e-fuel, to foster further advancement of green vehicle technology.

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Postgraduate YPEC 2021

PG04-Investigation of SAW Filter with Interdigital Transducer Parametric Variation by FEM Simulation and In-House Fabrication

SAW filter is widely used in wireless communication, especially in 5G and IoT applications. It is an important passive component in this wireless front-end circuit due to its compact size and high-quality factor. Since it shares the same fabrication processes with the integrated circuit’s industry, the SAW filters can be massively produced to further reduce the cost. In this project, evaluation of the in-house design and fabrication of SAW filter was studied. Detailed effect of interdigital transducers (IDTs) variation was investigated by FEM simulation. The parametric variation includes the presence of reflectors, IDT’s length, separation of ports, the number of reflectors and IDTs per port. The SAW filters were fabricated in the University Research Facility in Material Characterization and Device Fabrication (UMF) in The Hong Kong Polytechnic University (PolyU), which is the first in-house fabricated RF component. The capability of investigating the detailed SAW features has been demonstrated. The best fabricated SAW filter gives lower than 3 dB of insertion loss and more than 10 dB of return loss at 480 MHz without any external lumped elements at the ports for matching used in traditional SAW filter’s circuit.

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Postgraduate YPEC 2021

PG03-A Novel Energy-free and Environment-friendly Passive Radiative Cooling Paint for Building Energy Saving and Decarbonisation

This project aims to promote a novel energy-free and environment-friendly passive radiative cooling technology inspired by the Saharan Ant which uses the universe as the cooling source, and demonstrate a high-performance and low-cost passive radiative cooling paint (patented in HK) for building energy saving and decarbonization. The cooling paint, featuring the unmatched optical properties, is capable of effectively reflecting the sunlight and emitting the building’s thermal heat to the cold universe simultaneously. Credit to this dual effect, the building surface temperature can be reduced, relieving the energy consumption of building air-conditioning systems. More significantly, the efficiency and applicability of the cooling paint have been demonstrated in real building scenarios supported by CEDD and EMSD of the HKSAR government, in which at least 20 ⁰C of surface temperature reduction and ~8% of cooling energy saving could be achieved. Empowered by the previous achievements and rewards, including the success in Geneva inventions 2021 and other technological innovation competitions, we aspire to deliver remarkable environmental and social impacts by actively collaborating with various parties across the industries and obtaining public exposure. Our ultimate goal is to mitigate the environmental issues in Hong Kong, and facilitate the overall development of green buildings and sustainability.

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Postgraduate YPEC 2021

PG02-A Method for Online Auditory Assessment and Therapy on Pattern Recognition under COVID-19 Pandemic

The global Coronavirus disease (COVID-19) pandemic has impacted our society in various ways. In consequence, healthcare services with a face-to-face setting are forced to search for a new mean of delivery in order to ensure the safety of client and provider. A remote acoustic control method is proposed for health services involving auditory assessment and therapy through online conferencing software. Different video conferencing softwares have different sound responses as well as other limitations. The user’s computers also have its variation in the sound performance. These restrictions affect the use of this online platform to deliver health services required accurate, reliable and repeatable sound. In this project, a low cost processor is used to design the platform such that service providers could remotely play the desired audio files on the client’s side without suffering from the loss of sound in terms of frequency range and loudness due to the video-conferencing software. Experimental results show that this remote control of audio playback can be realized with a low cost processor called microcontroller unit (MCU) based on pattern recognition on client incoming audio frequency and it is able to deliver the audio files accurately in terms of frequency and amplitude.

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Postgraduate YPEC 2021

PG07-Electrifying the Nitrogen Cycle: An Electrochemical Endeavor

The advent of the Haber-Bosch (HB) process has made accessible all forms of nitrogenous derivatives (ammonia, nitrates, nitrites, and amines), revolutionizing the chemical industry. However, the depleting natural resources and growing environmental concerns demand a shift towards an energy-abated and environmental-friendly alternative to the HB process, hence the shift in the recent research focus. The electrochemical reduction pathway offers one of the most alluring prospects as a carbon-free, environment-friendly, energy-abated alternative to the HB process. In this context, we explore a rarely explored avenue; molten hydroxide system for electrochemical ammonia synthesis. The molten hydroxide systems boast the highest ammonia production rates from nitrates and nitrites, with the potential to revolutionize the ammonia industry.

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Postgraduate YPEC 2021

PG06-Development of a Thermal-camera-based Body Temperature Measurement System Using Embedded AI Technology

Amid the COVID-19 pandemic, body temperature monitoring is an effective measure to reduce the risk of COVID-19 spreading in the community. Two common ways to measure body temperature in public settings include non-contact infrared thermometers and thermal imaging systems. The use of non-contact infrared thermometers involves physical proximity, additional manpower and time, whereas the existing thermal imaging systems are either inaccurate or expensive. To address the above problems, an accurate and low-cost automatic fever screening system is developed to assist in preliminary health assessment. The system involves the integration of a RGB camera, a thermal camera, an embedded system board, and a cloud analytics platform. By utilizing temperature measurement and face detection, the system can extract forehead temperature and assess if the person being evaluated is wearing a mask or not. The system has conducted trial runs in various crowded settings including schools, restaurants, community centres, and commercial buildings. This study tries to lower the cost of developing an effective self checking station for fever screening by hardware trade-off and software optimization, to keep the cost within the market acceptance price. This solution is planned to be made widely accessible to serve our community during the COVID-19 period.