Zhu Wanyi

TechTalk – Urban Water Security and Smart Management in a Changing World: Case Study in the Yangtze River Economic Belt

Innovation Wing Two, TechTalk / By

February 24, 2025 (Monday) 10:30-11:30pm
Under the impact of global climate change, tremendous land use land cover changes, and extensive human interventions, urban areas face grand challenges in water security and green development. Ensuring urban water security requires ensuring quality and quantity of drinking water, sanitation, human well-being, water productivity, socio-economic values, ecosystems and environmental health, and mitigating water-related hazards. To resolve urban water security-related issues, a systematic framework by linking natural and social water cycles is urgently needed. Xia proposed the “Urban Water System, version 5.0” featuring “water quantity-quality-ecology” system approach by linking urban systems with natural river basin systems and applied it to the smart basin management, flash flood forecasting, and disaster mitigation. Besides, Xia led the development of the “Yangtze River Simulator,” which integrates sky-to-ground monitoring and comprehensive numerical simulation of hydrological-related processes in the Yangtze River Basin to foster the early warning and decision making of water security and water governance.

HKAE TechTalk – Breakthroughs from ChatGPT to DeepSeek and Higher Education Revolution

Innovation Wing Two, TechTalk / By

February 28, 2024 (Tuesday) 4:00-5:00pm
The rapid development of generative AI has ignited a new wave of technological innovations. Breakthroughs like ChatGPT and DeepSeek are opening doors to democratize and accelerate adoption across various industries and countries. This new era presents both challenges and opportunities for institutions of higher education, such as Lingnan University, where research and creativity are integral to daily life. The university acknowledges that knowledge is dynamic and evolving, not static, and disruptive technologies can displace existing professions while creating new ones.
Several open questions to be addressed include:
• Breakthroughs from ChatGPT to DeepSeek
• How will generative AI affect the curriculum?
• What education subjects would be sustained or diminished?
• How can we help students enhance critical thinking skills with generative AI?
• How does the digital revolution affect higher education in terms of skills-based and holistic education?

TechTalk – AI-Assisted Community Legal Information Access

Innovation Wing Two, TechTalk / By

February 20, 2025 (Thursday) 4:30-5:30pm
In the contemporary era, legal information, encompassing court judgments and legislation, is generally accessible online in numerous countries. However, the online availability of this information does not necessarily equate to effective public access to legal knowledge. It presents significant challenges for individuals without legal expertise to acquire legal knowledge due to two primary reasons. Firstly, the online content predominantly consists of primary legal sources, such as cases and statutes, which are typically written in formal legal terminology that can be challenging for the general public to comprehend. Secondly, the public may lack knowledge of the applicable legal principles in their specific legal situations. Given the vast number of documents, it becomes arduous for users to identify the relevant legal sources when seeking solutions to their legal challenges. In this presentation, we will demonstrate several AI tools that we have integrated into our online legal information platforms, specifically HKLII and CLIC. We will elucidate how these tools facilitate enhanced public access to legal information.

TechTalk – A Healthy Building is A Prerequisite and Mandatory for Achieving Sustainable Growth

Innovation Wing Two, TechTalk / By

January 7, 2025 (Tuesday) 2:30-3:30pm
The Healthy Buildings term was defined more than 40 years ago. It is relevant to ask whether it is still valid today in the present form and whether it needs any revisions and supplements, considering many changes and new challenges. This presentation will discuss the original definition and outline these new challenges, for example, resilience, monitoring, economic implications, and consequences of climate change and the pandemic risk. Some solutions will be presented with support from new research studies; the potential risks of the undertakings will also be discussed. One crucial issue discussed will be the inclusion of the need for healthy buildings in the decarbonization processes as an essential element of achieving sustainable development.

TechTalk – Thermal Insulation in Materials for Efficient Energy Conversion

Innovation Wing Two, TechTalk / By

December 19, 2024 (Thursday) 4:30-5:30pm
To enhance the thermoelectric conversion efficiency of materials, the thermal conduction needs to be suppressed, and the lattice dynamics and the thermal transport mechanisms must be better understood. Lattice thermal conduction of conventional solids is dominated by phonon propagation; however, diffuson-like thermal transport can become predominant in materials with ultralow thermal conductivity. New strategies for a simultaneous suppression of both propagative and diffusive thermal transports will be discussed in this talk based on state-of-the-art theories. Zintl compounds were recently found to exhibit exceptional thermoelectric properties. A thorough experimental study of the thermoelectric transport and carrier properties of Zintl compounds will be discussed. It will be shown that a high figure of merit over a broad temperature range can be realized through the suppression of the intrinsic carrier excitation.

TechTalk – Optimizing Distributed Large Model Training in AI Clouds

Innovation Wing Two, TechTalk / By

December 12, 2024 (Thursday) 4:30-5:30pm
Distributed training using a large number of devices has been widely adopted for learning large deep learning models. Improving distributed training efficiency is critical for time, resource and energy consumption of large model learning. In this talk, I will introduce recent research works in my group on optimizing distributed training parallelisms for effective training acceleration and maximal resource utilization. Especially, we have designed optimized strategies and systems for operator sharding, computation and communication scheduling for SPMD parallelism (e.g., in Mixture-of-Experts model training) in both homogeneous and heterogeneous AI clusters, as well as dynamic micro-batching and pipelining to tackle sequence length variation in multi-task model training (e.g., Large Language Model training).

TechTalk – Medical Image Representation Learning via Cross-supervision between Images and Text Reports

Innovation Wing Two, TechTalk / By

December 5, 2024 (Thursday) 4:30-5:30pm
Pre-training lays the foundation for recent successes in radiograph analysis supported by deep learning. It learns transferable image representations by conducting large-scale fully- or self-supervised learning on a source domain; however, supervised pre-training requires a complex and labour-intensive two-stage human-assisted annotation process, whereas self-supervised learning cannot compete with the supervised paradigm. To tackle these issues, we propose a cross-supervised methodology called reviewing free-text reports for supervision (REFERS), which acquires free supervision signals from the original radiology reports accompanying the radiographs. The proposed approach employs a vision transformer and is designed to learn joint representations from multiple views within every patient study. REFERS outperforms its transfer learning and self-supervised learning counterparts on four well-known X-ray datasets under extremely limited supervision. Moreover, REFERS even surpasses methods based on a source domain of radiographs with human-assisted structured labels; it therefore has the potential to replace canonical pre-training methodologies.

TechTalk – Wafer-scale Structural Coloration Using Gray-scale Lithographic Fabrication

Innovation Wing Two, TechTalk / By

November 28, 2024 (Thursday) 4:30-5:30pm
Structural colors use nanostructured building blocks or thin films to resonantly reflect or scatter light to generate colors and can exhibit higher resolution, saturation, and durability than pigment-based colors. To create structural color based paintings, it is essential to develop a capability of spatially varying the dimensions of these nanosized structures. Recently we reported a high-throughput and wafer-scale nanopatterning method by combining interference lithography and grayscale-patterned secondary exposure (IL-GPSE) to spatially modulate nanostructure feature sizes on large scale while maintaining sufficiently high resolution. Here, we employ the IL-GPSE method in the fabrication of wafer-scale structural color paintings, which can improve the patterning efficiency by orders of magnitude when compared with e-beam lithography. The fabrication techniques developed in this work have unique potentials for broader applications in biomedical sensing, spectral filtering, anti-counterfeiting or encryption, etc.

HKAE TechTalk – The Grain Boundary Ratchet: How to Engineer Grain Size

Innovation Wing Two, TechTalk / By

January 9, 2024 (Thursday) 2:30-3:30pm
We demonstrate that grain boundaries (GBs) behave as Brownian ratchets, exhibiting direction-dependent mobilities and unidirectional motion under oscillatory driving forces or cyclic thermal annealing. We observed these phenomena for nearly all nonsymmetric GBs but not for symmetric ones. Our observations build on molecular dynamics and phase-field crystal simulations for a wide range of GB types and driving forces in both bicrystal and polycrystalline microstructures. We corroborate these simulation results through in situ experimental observations. We analyze these results with a Markov chain model and explore the implications of GB ratchet behavior for materials processing and microstructure tailoring.

HKAE TechTalk – Vision-driven Robots: Challenges, Technologies and Applications

Innovation Wing Two, TechTalk / By

November 19 2024 (Tuesday) 4:00-5:00pm
Robotics and AI technologies are rapidly advancing in recent years, but intelligence levels of robots are still far below humans’ expectations. One of the major reasons is that a robot is not good at coordinating visual information captured by its vision systems, i.e. eyes, with motions of its arms, hands, and legs or wheels. Accurate, robust and efficient perception and effective use of the visual information is crucial for robots to successfully perform tasks in natural environments. This talk presents technical challenges in vision-driven robotics, our on-going work and latest results in vision-driven robot manipulation and vision-guided robot navigation, and applications of the technologies in manufacturing, logistics and robotic surgery.