Electrical and Electronic Engineering

TechTalk – MRI at 0.05 Tesla for Accessible Healthcare: Back to the Future?

October 10, 2024 (Thursday) 4:30-5:30pm
Despite a half-century of advancements, global MRI accessibility remains limited, hindering its full potential in health care. Initially, MRI development focused on low fields around 0.05 Tesla, but progress halted after the introduction of the 1.5 Tesla whole-body superconducting scanner in 1983. Using permanent 0.05 Tesla magnets and deep learning for electromagnetic interference elimination, we developed highly simplified 0.05 Tesla MRI systems that operate using a standard wall power outlet and without radiofrequency and magnetic shielding. We demonstrated its wide-ranging applicability for imaging both brain (Nature Communications 2021) and various anatomical structures at whole-body level (Science 2024). Furthermore, we developed three-dimensional deep learning reconstruction methodologies to boost image quality by harnessing extensive high-field MRI data (MRM 2023, Science Advances 2023, Science 2024). We hope these advances will eventually lead to a new class of affordable and computing–powered ultra-low-field MRI scanners for point-of-care applications, addressing unmet clinical needs in diverse health care settings.

Young Scholar TechTalk – Learning Out-of-Distribution Object Detectors from Foundation Models

September 16 2024 (Monday) 4:30-5:30pm
Out-of-distribution (OOD) object detection is a challenging task due to the absence of open-set OOD data. Inspired by recent advancements in text-to-image generative models, such as Stable Diffusion, we study the potential of generative models trained on large-scale open-set data to synthesize OOD samples, thereby enhancing OOD object detection. We introduce SyncOOD, a simple data curation method that capitalizes on the capabilities of large foundation models to automatically extract meaningful OOD data from text-to-image generative models. This offers the model access to open-world knowledge encapsulated within off-the-shelf foundation models. The synthetic OOD samples are then employed to augment the training of a lightweight, plug-and-play OOD detector, thus effectively optimizing the in-distribution (ID)/OOD decision boundaries. Extensive experiments across multiple benchmarks demonstrate that SyncOOD significantly outperforms existing methods, establishing new state-of-the-art performance with minimal synthetic data usage.

TechTalk – Building Functional Devices with Colloidal Nanocrystals from the Bottom Up

June 27, 2024 (Thursday) 4:30-5:30pm
Speaker: Professor Leo Tianshuo Zhao, Assistant Professor, Department of Electrical and Electronic Engineering, Faculty of Engineering, HKU
This talk will highlight our previous works about developing heavy-metal-free NC materials and efficient surface modification for near-infrared optoelectronic devices and advancing scale-up fabrication of NC sensor devices for IoT technologies. The talk will also include our recent work on the nanoprinting of NCs to acheive multi-material and multi-functional devices.

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.

TechTalk – Learning to Simulate and Understand the 3D World

June 06, 2024 (Thursday) 4:30-5:30pm
Humans live in a 3D world, continually acquiring diverse skills and engaging in various activities through perceiving, understanding, and interacting with it. Our long-term research objective is centered on simulating the 3D world and empowering AI systems with 3D spatial understanding capabilities. In this talk, I will start by discussing our recent research efforts in creating 3D interactive environments by reconstruction, decomposition, and generation. Subsequently, I will explore how we can equip machines with the ability to comprehend and reason within a 3D environment by adopting a data-centric approach. Lastly, I will examine the possibilities of integrating 3D environment simulation and understanding to facilitate the emergence of closed-loop active intelligence. In summary, this talk will encompass our latest efforts in 3D reconstruction, comprehension, and creation, ultimately aiming for AI systems that can effectively navigate and engage with our 3D world.

TechTalk – Towards Controllable and Compositional Visual Content Generation

May 30, 2024 (Thursday) 4:30-5:30pm
Visual content generation has achieved great success in the past few years, but current visual generation models still lack controllability and compositionality. In real applications, we desire highly controllable visual generation models which allow users to control the generated contents in a fine-grained manner. We also desire models which can effectively compose objects with different attributes and relationships into a complex and coherent scene. In this talk, I will introduce our several works towards controllable and compositional visual content generation. I will introduce T2I-CompBench for benchmarking compositional text-to-image generation. I will also introduce our recent works on drag-based video editing, controllable 3D generation, and training-free massive concept editing in text-to-image diffusion models.

TechTalk – Power Network Stability: A Network Science-based Approach

May 23, 2024 (Thursday) 4:30-5:30pm
Future power systems will need to accommodate a high penetration of renewables, new loads, and increased interconnections, which can make the system less resilient to changes and faults. However, traditional power system stability analysis methods may not be sufficient to ensure stable and robust operations in these new environments. To address this, network science is emerging as a promising area for developing new solutions. This seminar proposes a new framework for power system stability analysis that integrates network-based models with traditional power system theory. The focus will be on understanding how power network topology impacts the stability of the system, shedding new light on instability mechanisms.

TechTalk – Heterogeneous Silicon Photonic Integrated Circuits: Progress and Prospects

April 18 2024 (Thursday) 5:00-6:00pm
Photonics has played a vital role in shaping information technology infrastructure. Now it is considered crucial for addressing the emerging bandwidth constraints and power consumption challenges in hyperscale datacenters and high-performance computing systems. Central to these photonic solutions are photonic integrated circuits (PICs) which have seen dramatic progress in the past decades. A heterogeneous silicon photonics platform that integrates materials with superior properties is projected to fully unlock the application potentials of PICs. Examples include combining novel light sources (e.g., optical frequency combs and narrow-linewidth lasers) with other functional components on a single chip, to construct PICs with complete optical functionalities and advantages in terms of integration density, energy consumption and performance. In this talk, I will introduce the recent progress of heterogeneous silicon photonic integrated circuits and outline the prospects.

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.

TechTalk – Robotics and AI for Real-world Challenges

Current AI cannot provide a complete solution for robotics, although AI is a useful tool for real-world challenges that cannot be solved by traditional methods. We will discuss how AI can be applied to solve real-world problems using robotic systems developed by our team so far. Inspired by a dance partner robot developed for the Aichi Expo in 2005, a co-worker robot “PaDY” was developed for the automotive assembly process. Intention estimation was a key to these collaborative robots. AI has also led to the development of robotic applications in manufacturing, such as computer vision for bin picking, grasp planning, robot motion planning, and assembly of textureless industrial parts using visual servoing. Recent advances in AI are making it possible to tackle the manipulation of soft materials. The JC STEM Lab of Robotics for Soft Materials funded by the Hong Kong Jockey Club Charities Trust covers this new field.