Showing 1–13 of 13 results for author: Teo, T H

Federated Learning Inspired Fuzzy Systems: Decentralized Rule Updating for Privacy and Scalable Decision Making

Authors: Arthur Alexander Lim, Zhen Bin It, Jovan Bowen Heng, Tee Hui Teo

Abstract: Fuzzy systems are a way to allow machines, systems and frameworks to deal with uncertainty, which is not possible in binary systems that most computers use. These systems have already been deployed for certain use cases, and fuzzy systems could be further improved as proposed in this paper. Such technologies to draw inspiration from include machine learning and federated learning. Machine learning… ▽ More Fuzzy systems are a way to allow machines, systems and frameworks to deal with uncertainty, which is not possible in binary systems that most computers use. These systems have already been deployed for certain use cases, and fuzzy systems could be further improved as proposed in this paper. Such technologies to draw inspiration from include machine learning and federated learning. Machine learning is one of the recent breakthroughs of technology and could be applied to fuzzy systems to further improve the results it produces. Federated learning is also one of the recent technologies that have huge potential, which allows machine learning training to improve by reducing privacy risk, reducing burden on networking infrastructure, and reducing latency of the latest model. Aspects from federated learning could be used to improve federated learning, such as applying the idea of updating the fuzzy rules that make up a key part of fuzzy systems, to further improve it over time. This paper discusses how these improvements would be implemented in fuzzy systems, and how it would improve fuzzy systems. It also discusses certain limitations on the potential improvements. It concludes that these proposed ideas and improvements require further investigation to see how far the improvements are, but the potential is there to improve fuzzy systems. △ Less

Submitted 9 July, 2025; originally announced July 2025.

Pseudo Random Number Generator using Internet-of-Things Techniques on Portable Field-Programmable-Gate-Array Platform

Authors: Tee Hui Teo

Abstract: This paper conducts a comparative study of three IoT-based PRNG models, including Logistic Map, Double Pendulum, and Multi-LFSR, implemented on an FPGA platform. Comparisons are made across key performance metrics like randomness, latency, power consumption, hardware resource usage, energy efficiency, scalability, and application suitability. Compared to Multi-LFSR, Logistic Map, and Double Pendul… ▽ More This paper conducts a comparative study of three IoT-based PRNG models, including Logistic Map, Double Pendulum, and Multi-LFSR, implemented on an FPGA platform. Comparisons are made across key performance metrics like randomness, latency, power consumption, hardware resource usage, energy efficiency, scalability, and application suitability. Compared to Multi-LFSR, Logistic Map, and Double Pendulum Models provide perfect quality randomness, which is quite apt for high-security grade applications; however, the requirements of these models concerning power and hardware resources are also considerably high. By contrast, the Multi-LFSR comes into its own due to its lower latency, power consumption, and resource-efficient design. It is, therefore, suited for embedded or real-time applications. Furthermore, environmental sensors will also be introduced as entropy sources for the PRNGs to enhance the randomness of the systems, particularly in IoT-enabled battery-powered FPGA platforms. The experimental results confirm that the Multi-LFSR model has the highest energy efficiency, while the Logistic Map and Double Pendulum outperform in generating numbers with very high security. The study thus provides a deeper insight into decision-making for selecting PRNG models. △ Less

Submitted 2 April, 2025; originally announced May 2025.

Comments: 7 pages

FairQueue: Rethinking Prompt Learning for Fair Text-to-Image Generation

Authors: Christopher T. H Teo, Milad Abdollahzadeh, Xinda Ma, Ngai-man Cheung

Abstract: Recently, prompt learning has emerged as the state-of-the-art (SOTA) for fair text-to-image (T2I) generation. Specifically, this approach leverages readily available reference images to learn inclusive prompts for each target Sensitive Attribute (tSA), allowing for fair image generation. In this work, we first reveal that this prompt learning-based approach results in degraded sample quality. Our… ▽ More Recently, prompt learning has emerged as the state-of-the-art (SOTA) for fair text-to-image (T2I) generation. Specifically, this approach leverages readily available reference images to learn inclusive prompts for each target Sensitive Attribute (tSA), allowing for fair image generation. In this work, we first reveal that this prompt learning-based approach results in degraded sample quality. Our analysis shows that the approach's training objective -- which aims to align the embedding differences of learned prompts and reference images -- could be sub-optimal, resulting in distortion of the learned prompts and degraded generated images. To further substantiate this claim, as our major contribution, we deep dive into the denoising subnetwork of the T2I model to track down the effect of these learned prompts by analyzing the cross-attention maps. In our analysis, we propose a novel prompt switching analysis: I2H and H2I. Furthermore, we propose new quantitative characterization of cross-attention maps. Our analysis reveals abnormalities in the early denoising steps, perpetuating improper global structure that results in degradation in the generated samples. Building on insights from our analysis, we propose two ideas: (i) Prompt Queuing and (ii) Attention Amplification to address the quality issue. Extensive experimental results on a wide range of tSAs show that our proposed method outperforms SOTA approach's image generation quality, while achieving competitive fairness. More resources at FairQueue Project site: https://sutd-visual-computing-group.github.io/FairQueue △ Less

Submitted 24 October, 2024; originally announced October 2024.

Comments: Accepted in NeurIPS24

How to Mitigate the Dependencies of ChatGPT-4o in Engineering Education

Authors: Maoyang Xiang, T. Hui Teo

Abstract: The rapid evolution of large multimodal models (LMMs) has significantly impacted modern teaching and learning, especially in computer engineering. While LMMs offer extensive opportunities for enhancing learning, they also risk undermining traditional teaching methods and fostering excessive reliance on automated solutions. To counter this, we have developed strategies within curriculum to reduce t… ▽ More The rapid evolution of large multimodal models (LMMs) has significantly impacted modern teaching and learning, especially in computer engineering. While LMMs offer extensive opportunities for enhancing learning, they also risk undermining traditional teaching methods and fostering excessive reliance on automated solutions. To counter this, we have developed strategies within curriculum to reduce the dependencies on LMMs that represented by ChatGPT-4o. These include designing course topics that encourage hands-on problem-solving. The proposed strategies were demonstrated through an actual course implementation. Preliminary results show that the methods effectively enhance student engagement and understanding, balancing the benefits of technology with the preservation of traditional learning principles. △ Less

Submitted 21 May, 2024; originally announced July 2024.

Comments: 6 pages, 1 figure, 1 table

Digital ASIC Design with Ongoing LLMs: Strategies and Prospects

Authors: Maoyang Xiang, Emil Goh, T. Hui Teo

Abstract: The escalating complexity of modern digital systems has imposed significant challenges on integrated circuit (IC) design, necessitating tools that can simplify the IC design flow. The advent of Large Language Models (LLMs) has been seen as a promising development, with the potential to automate the generation of Hardware Description Language (HDL) code, thereby streamlining digital IC design. Howe… ▽ More The escalating complexity of modern digital systems has imposed significant challenges on integrated circuit (IC) design, necessitating tools that can simplify the IC design flow. The advent of Large Language Models (LLMs) has been seen as a promising development, with the potential to automate the generation of Hardware Description Language (HDL) code, thereby streamlining digital IC design. However, the practical application of LLMs in this area faces substantial hurdles. Notably, current LLMs often generate HDL code with small but critical syntax errors and struggle to accurately convey the high-level semantics of circuit designs. These issues significantly undermine the utility of LLMs for IC design, leading to misinterpretations and inefficiencies. In response to these challenges, this paper presents targeted strategies to harness the capabilities of LLMs for digital ASIC design. We outline approaches that improve the reliability and accuracy of HDL code generation by LLMs. As a practical demonstration of these strategies, we detail the development of a simple three-phase Pulse Width Modulation (PWM) generator. This project, part of the "Efabless AI-Generated Open-Source Chip Design Challenge," successfully passed the Design Rule Check (DRC) and was fabricated, showcasing the potential of LLMs to enhance digital ASIC design. This work underscores the feasibility and benefits of integrating LLMs into the IC design process, offering a novel approach to overcoming the complexities of modern digital systems. △ Less

Submitted 25 April, 2024; originally announced May 2024.

Comments: 8 pages, 2 figures, 1 table

FPGA Digital Dice using Pseudo Random Number Generator

Authors: Michael Lim Kee Hian, Ten Wei Lin, Zachary Wu Xuan, Stephanie-Ann Loy, Maoyang Xiang, T. Hui Teo

Abstract: The goal of this project is to design a digital dice that displays dice numbers in real-time. The number is generated by a pseudo-random number generator (PRNG) using XORshift algorithm that is implemented in Verilog HDL on an FPGA. The digital dice is equipped with tilt sensor, display, power management circuit, and rechargeable battery hosted in a 3D printed dice casing. By shaking the digital d… ▽ More The goal of this project is to design a digital dice that displays dice numbers in real-time. The number is generated by a pseudo-random number generator (PRNG) using XORshift algorithm that is implemented in Verilog HDL on an FPGA. The digital dice is equipped with tilt sensor, display, power management circuit, and rechargeable battery hosted in a 3D printed dice casing. By shaking the digital dice, the tilt sensor signal produces a seed for the PRNG. This digital dice demonstrates a set of possible random numbers of 2, 4, 6, 8, 10, 12, 20, 100 that simulate the number of dice sides. The kit is named SUTDicey. △ Less

Submitted 1 May, 2024; originally announced May 2024.

Comments: 15 pages, 5 figures

Logistic Map Pseudo Random Number Generator in FPGA

Authors: Mateo Jalen Andrew Calderon, Lee Jun Lei Lucas, Syarifuddin Azhar Bin Rosli, Stephanie See Hui Ying, Jarell Lim En Yu, Maoyang Xiang, T. Hui Teo

Abstract: This project develops a pseudo-random number generator (PRNG) using the logistic map, implemented in Verilog HDL on an FPGA and processes its output through a Central Limit Theorem (CLT) function to achieve a Gaussian distribution. The system integrates additional FPGA modules for real-time interaction and visualisation, including a clock generator, UART interface, XADC, and a 7-segment display dr… ▽ More This project develops a pseudo-random number generator (PRNG) using the logistic map, implemented in Verilog HDL on an FPGA and processes its output through a Central Limit Theorem (CLT) function to achieve a Gaussian distribution. The system integrates additional FPGA modules for real-time interaction and visualisation, including a clock generator, UART interface, XADC, and a 7-segment display driver. These components facilitate the direct display of PRNG values on the FPGA and the transmission of data to a laptop for histogram analysis, verifying the Gaussian nature of the output. This approach demonstrates the practical application of chaotic systems for generating Gaussian-distributed pseudo-random numbers in digital hardware, highlighting the logistic map's potential in PRNG design. △ Less

Submitted 30 April, 2024; originally announced April 2024.

Comments: 10 pages, 6 figures

Hardware Implementation of Double Pendulum Pseudo Random Number Generator

Authors: Jarrod Lim, Tom Manuel Opalla Piccio, Chua Min Jie Michelle, Maoyang Xiang, T. Hui Teo

Abstract: The objective of this project is to utilize an FPGA board which is the CMOD A7 35t to obtain a pseudo random number which can be used for encryption. We aim to achieve this by leveraging the inherent randomness present in environmental data captured by sensors. This data will be used as a seed to initialize an algorithm implemented on the CMOD A7 35t FPGA board. The project will focus on interfaci… ▽ More The objective of this project is to utilize an FPGA board which is the CMOD A7 35t to obtain a pseudo random number which can be used for encryption. We aim to achieve this by leveraging the inherent randomness present in environmental data captured by sensors. This data will be used as a seed to initialize an algorithm implemented on the CMOD A7 35t FPGA board. The project will focus on interfacing the sensors with the FPGA and developing suitable algorithms to ensure the generated numbers exhibit strong randomness properties. △ Less

Submitted 25 April, 2024; originally announced April 2024.

Comments: 15 pages, 12 figure

SF-MMCN: Low-Power Sever Flow Multi-Mode Diffusion Model Accelerator

Authors: Huan-Ke Hsu, I-Chyn Wey, T. Hui Teo

Abstract: Generative Artificial Intelligence (AI) has become incredibly popular in recent years, and the significance of traditional accelerators in dealing with large-scale parameters is urgent. With the diffusion model's parallel structure, the hardware design challenge has skyrocketed because of the multiple layers operating simultaneously. Convolution Neural Network (CNN) accelerators have been designed… ▽ More Generative Artificial Intelligence (AI) has become incredibly popular in recent years, and the significance of traditional accelerators in dealing with large-scale parameters is urgent. With the diffusion model's parallel structure, the hardware design challenge has skyrocketed because of the multiple layers operating simultaneously. Convolution Neural Network (CNN) accelerators have been designed and developed rapidly, especially for high-speed inference. Often, CNN models with parallel structures are deployed. In these CNN accelerators, many Processing Elements (PE) are required to perform parallel computations, mainly the multiply and accumulation (MAC) operation, resulting in high power consumption and a large silicon area. In this work, a Server Flow Multi-Mode CNN Unit (SF-MMCN) is proposed to reduce the number of PE while improving the operation efficiency of the CNN accelerator. The pipelining technique is introduced into Server Flow to process parallel computations. The proposed SF-MMCN is implemented with TSMC 90-nm CMOS technology. It is evaluated with VGG-16, ResNet-18, and U-net. The evaluation results show that the proposed SF-MMCN can reduce the power consumption by 92%, and the silicon area by 70%, while improving the efficiency of operation by nearly 81 times. A new FoM, area efficiency (GOPs/mm^2) is also introduced to evaluate the performance of the accelerator in terms of the ratio throughput (GOPs) and silicon area (mm^2). In this FoM, SF-MMCN improves area efficiency by 18 times (18.42). △ Less

Submitted 26 September, 2024; v1 submitted 8 March, 2024; originally announced March 2024.

Comments: 16 pages, 16 figures; extend the CNN to process Diffusion Model (possible this is the first reported hardware Diffusion Model implementation)

From English to ASIC: Hardware Implementation with Large Language Model

Authors: Emil Goh, Maoyang Xiang, I-Chyn Wey, T. Hui Teo

Abstract: In the realm of ASIC engineering, the landscape has been significantly reshaped by the rapid development of LLM, paralleled by an increase in the complexity of modern digital circuits. This complexity has escalated the requirements for HDL coding, necessitating a higher degree of precision and sophistication. However, challenges have been faced due to the less-than-optimal performance of modern la… ▽ More In the realm of ASIC engineering, the landscape has been significantly reshaped by the rapid development of LLM, paralleled by an increase in the complexity of modern digital circuits. This complexity has escalated the requirements for HDL coding, necessitating a higher degree of precision and sophistication. However, challenges have been faced due to the less-than-optimal performance of modern language models in generating hardware description code, a situation further exacerbated by the scarcity of the corresponding high-quality code datasets. These challenges have highlighted the gap between the potential of LLMs to revolutionize digital circuit design and their current capabilities in accurately interpreting and implementing hardware specifications. To address these challenges, a strategy focusing on the fine-tuning of the leading-edge nature language model and the reshuffling of the HDL code dataset has been developed. The fine-tuning aims to enhance models' proficiency in generating precise and efficient ASIC design, while the dataset reshuffling is intended to broaden the scope and improve the quality of training material. The model demonstrated significant improvements compared to the base model, with approximately 10% to 20% increase in accuracy across a wide range of temperature for the pass@1 metric. This approach is expected to facilitate a simplified and more efficient LLM-assisted framework for complex circuit design, leveraging their capabilities to meet the sophisticated demands of HDL coding and thus streamlining the ASIC development process. △ Less

Submitted 11 March, 2024; originally announced March 2024.

Comments: 15 pages, 1 figure

On Measuring Fairness in Generative Models

Authors: Christopher T. H. Teo, Milad Abdollahzadeh, Ngai-Man Cheung

Abstract: Recently, there has been increased interest in fair generative models. In this work, we conduct, for the first time, an in-depth study on fairness measurement, a critical component in gauging progress on fair generative models. We make three contributions. First, we conduct a study that reveals that the existing fairness measurement framework has considerable measurement errors, even when highly a… ▽ More Recently, there has been increased interest in fair generative models. In this work, we conduct, for the first time, an in-depth study on fairness measurement, a critical component in gauging progress on fair generative models. We make three contributions. First, we conduct a study that reveals that the existing fairness measurement framework has considerable measurement errors, even when highly accurate sensitive attribute (SA) classifiers are used. These findings cast doubts on previously reported fairness improvements. Second, to address this issue, we propose CLassifier Error-Aware Measurement (CLEAM), a new framework which uses a statistical model to account for inaccuracies in SA classifiers. Our proposed CLEAM reduces measurement errors significantly, e.g., 4.98% $\rightarrow$ 0.62% for StyleGAN2 w.r.t. Gender. Additionally, CLEAM achieves this with minimal additional overhead. Third, we utilize CLEAM to measure fairness in important text-to-image generator and GANs, revealing considerable biases in these models that raise concerns about their applications. Code and more resources: https://sutd-visual-computing-group.github.io/CLEAM/. △ Less

Submitted 30 October, 2023; originally announced October 2023.

Comments: Accepted in NeurIPS23

A Survey on Generative Modeling with Limited Data, Few Shots, and Zero Shot

Authors: Milad Abdollahzadeh, Guimeng Liu, Touba Malekzadeh, Christopher T. H. Teo, Keshigeyan Chandrasegaran, Ngai-Man Cheung

Abstract: Generative modeling in machine learning aims to synthesize new data samples that are statistically similar to those observed during training. While conventional generative models such as GANs and diffusion models typically assume access to large and diverse datasets, many real-world applications (e.g. in medicine, satellite imaging, and artistic domains) operate under limited data availability and… ▽ More Generative modeling in machine learning aims to synthesize new data samples that are statistically similar to those observed during training. While conventional generative models such as GANs and diffusion models typically assume access to large and diverse datasets, many real-world applications (e.g. in medicine, satellite imaging, and artistic domains) operate under limited data availability and strict constraints. In this survey, we examine Generative Modeling under Data Constraint (GM-DC), which includes limited-data, few-shot, and zero-shot settings. We present a unified perspective on the key challenges in GM-DC, including overfitting, frequency bias, and incompatible knowledge transfer, and discuss how these issues impact model performance. To systematically analyze this growing field, we introduce two novel taxonomies: one categorizing GM-DC tasks (e.g. unconditional vs. conditional generation, cross-domain adaptation, and subject-driven modeling), and another organizing methodological approaches (e.g. transfer learning, data augmentation, meta-learning, and frequency-aware modeling). Our study reviews over 230 papers, offering a comprehensive view across generative model types and constraint scenarios. We further analyze task-approach-method interactions using a Sankey diagram and highlight promising directions for future work, including adaptation of foundation models, holistic evaluation frameworks, and data-centric strategies for sample selection. This survey provides a timely and practical roadmap for researchers and practitioners aiming to advance generative modeling under limited data. Project website: https://sutd-visual-computing-group.github.io/gmdc-survey/. △ Less

Submitted 14 February, 2026; v1 submitted 26 July, 2023; originally announced July 2023.

Comments: Accepted to Transactions on Machine Learning Research (TMLR)

Journal ref: Transactions on Machine Learning Research (TMLR), 2025

Measuring Fairness in Generative Models

Authors: Christopher T. H Teo, Ngai-Man Cheung

Abstract: Deep generative models have made much progress in improving training stability and quality of generated data. Recently there has been increased interest in the fairness of deep-generated data. Fairness is important in many applications, e.g. law enforcement, as biases will affect efficacy. Central to fair data generation are the fairness metrics for the assessment and evaluation of different gener… ▽ More Deep generative models have made much progress in improving training stability and quality of generated data. Recently there has been increased interest in the fairness of deep-generated data. Fairness is important in many applications, e.g. law enforcement, as biases will affect efficacy. Central to fair data generation are the fairness metrics for the assessment and evaluation of different generative models. In this paper, we first review fairness metrics proposed in previous works and highlight potential weaknesses. We then discuss a performance benchmark framework along with the assessment of alternative metrics. △ Less

Submitted 16 July, 2021; originally announced July 2021.

Comments: Accepted in ICML 2021 Workshop - Machine Learning for Data: Automated Creation, Privacy, Bias