VLDB 2026 Research / reviewers in the wild / expert
Changchun Zhou 0001
dblp:157/3662-1
· DBLP profile ↗
12ranked-venue papers
3as first author
12since 2021 · last 2026
0009-0005-3968-5048ORCID · verified
Domains — the database's venue-derived domains; a paper can count in several
Systems, architecture and hardware · 9 · 2 first-author · 9 since 2021Software engineering, systems software and programming languages · 2 · 2 since 2021Graphics, computer vision, multimedia, augmented reality and games · 2 · 2 since 2021Computer networks · 1 · 1 first-author · 1 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | FractalCloud: A Fractal-Inspired Architecture for Efficient Large-Scale Point Cloud ProcessingabstractThree-dimensional (3D) point clouds are increasingly used in applications such as autonomous driving, robotics, and virtual reality (VR). Point-based neural networks (PNNs) have demonstrated strong performance in point cloud analysis, originally targeting small-scale inputs. However, as PNNs evolve to process large-scale point clouds with hundreds of thousands of points, all-to-all computation and global memory access in point cloud processing introduce substantial overhead, causing$O\left(n^{2}\right)$computational complexity and memory traffic where$n$is the number of points. Existing accelerators, primarily optimized for small-scale workloads, overlook this challenge and scale poorly due to inefficient partitioning and non-parallel architectures. To address these issues, we propose FractalCloud, a fractal-inspired hardware architecture for efficient large-scale 3D point cloud processing. FractalCloud introduces two key optimizations: (1) a co-designed Fractal method for shape-aware and hardware-friendly partitioning, and (2) block-parallel point operations that decompose and parallelize all point operations. A dedicated hardware design with on-chip fractal and flexible parallelism further enables fully parallel processing within limited memory resources. Implemented in 28 nm technology as a chip layout with a core area of$1.5 ~\text{mm}^{2}$, FractalCloud achieves$21.7 \times$speedup and$27 \times$energy reduction over state-of-the-art accelerators while maintaining network accuracy, demonstrating its scalability and efficiency for PNN inference. The code for FractalCloud is available at https://github.com/Yuzhe-Fu/FractalCloud. Yuzhe Fu, Changchun Zhou 0001, Hancheng Ye, Bowen Duan 0003, Qiyu Huang, Chiyue Wei, Cong Guo 0003, Hai Li 0001, Yiran Chen 0001 |
HPCA | 2 |
| 2026 | NP-CAM: Efficient and Scalable DNA Classification using a NoC-Partitioned CAM ArchitectureabstractThe rapid advancement in genomic sequencing technologies has resulted in an explosion of data, creating substantial computational bottlenecks in DNA analysis workloads. Applications such as DNA classification are particularly impacted due to their reliance on intensive, large-scale pattern matching. Existing hardware accelerator and software solutions are increasingly unable to manage the scale and energy demands of these datasets, highlighting the need for architectures that can perform faster and more efficient pattern matching. To address these challenges, we propose NP-CAM: a data-optimized, CAMbased accelerator designed for parallel and energy-efficient DNA classification. NP-CAM harnesses a network-on-chip to implement a novel optimized indexing and CAM partitioning scheme that reduces the active search space, allowing significant scalability. We demonstrate results for NP-CAM on commodity 10T binary CAM cell designs. Our experimental evaluations show that NPCAM achieves a simultaneous$65 \times$improvement in sequence throughput and an over$173 \times$improvement in energy efficiency over state-of-the-art hardware solutions on existing small viral workloads. We go on to demonstrate feasibility for larger bacterial and fungal workloads, enabling scalable DNA classification in the era of large-scale genomic data. Benjamin F. Morris III, Tergel Molom-Ochir, Changchun Zhou 0001, Yiran Chen 0001, Alex K. Jones, Hai Li 0001 |
HPCA | 3 |
| 2026 | Focus: A Streaming Concentration Architecture for Efficient Vision-Language ModelsabstractVision-Language Models (VLMs) have demonstrated strong performance on tasks such as video captioning and visual question answering. However, their growing scale and video-level inputs lead to significant computational and memory overhead, posing challenges for real-time deployment on hardware accelerators. While prior work attempts to reduce redundancy via token pruning or merging, these methods typically operate at coarse granularity and incur high runtime overhead due to global token-level operations. In this study, we propose Focus, a Streaming Concentration Architecture that efficiently accelerates VLM inference through progressive, fine-grained redundancy elimination. Focus introduces a multilevel concentration paradigm that hierarchically compresses vision-language inputs at three levels: (1) semantic-guided token pruning based on textual prompts, (2) spatial-temporal blocklevel concentration using localized comparisons, and (3) vectorlevel redundancy removal via motion-aware matching. All concentration steps are tightly co-designed with the architecture to support streaming-friendly, on-chip execution. Focus leverages GEMM tiling, convolution-style layout, and cross-modal attention to minimize off-chip access while enabling high throughput. Implemented as a modular unit within a systolic-array accelerator, Focus achieves$2.4 \times$speedup and$3.3 \times$reduction in energy, significantly outperforming state-of-the-art accelerator in both performance and energy efficiency. Full-stack implementation of Focus is open-sourced at https://github.com/dubcyfor3/Focus. Chiyue Wei, Cong Guo 0003, Junyao Zhang 0003, Haoxuan Shan, Qinsi Wang, Changchun Zhou 0001, Hai Li 0001, Yiran Chen 0001 |
HPCA | 9 |
| 2026 | EVA: Accelerating LLM Decoding via an Efficient Vector Quantization Architecture
Bowen Duan 0003, Cong Guo 0003, Chiyue Wei, Haoxuan Shan, Yuzhe Fu, Xinhua Chen, Changchun Zhou 0001, Hai Li 0001, Yiran Chen 0001 |
ISCA | 9 |
| 2026 | A CMOS Voltage Reference Featuring a Tandem Differential Structure With Two-Stage Stacked Diode-Connected MOSFETs CoreabstractIn this paper, A CMOS voltage reference (CVR) with two-stage self-biased stacked diode connected MOS transistors (SDMTs) which actively compensates for process, voltage, and temperature (PVT) variations via a tandem differential structure (TDS) is proposed. The SDMTs core biased by new pseudo cascode current mirror guarantees better suppression against supply change and generates two reference voltages. The TDS, composed of two tandem NMOS transistors, serves as an output stage, differentially processing these voltages and compensating the final reference against PVT variations. Thus, the deviation of final reference voltage from PVT change is largely reduced. The proposed CVR is fabricated in a 0.18-$\mu $m CMOS process occupying a total area of$0.0048~\mathbf {mm^{2} } $. Measurement results from 7 chips demonstrate that the design can achieve an average temperature coefficient of 67 ppm/° C from −40° C to 140° C without trimming networks. Line sensitivity and power supply rejection ratio are 0.009 %/V with a supply range of 1.3V to 2.5 V and -83 dB at 100 Hz. 1% settling time only takes 0.28ms. The average reference voltage is 294 mV. Qun Zhou 0001, Yaoze Liu, Kang Zeng, Xiaojian Zhu, Changchun Zhou 0001, Qing Hua |
IEEE Trans. Circuits Syst. I Regul. Pap. | 5 |
| 2025 | Ecco: Improving Memory Bandwidth and Capacity for LLMs via Entropy-Aware Cache CompressionabstractLarge language models (LLMs) have demonstrated transformative capabilities across diverse artificial intelligence applications, yet their deployment is hindered by substantial memory and computational demands, especially in resource-constrained environments.Quantization techniques have emerged as a critical solution, reducing data precision to enhance memory and computational efficiency.However, existing methods often suffer from high runtime overheads and potential accuracy degradation.To address these challenges, we propose Ecco, an entropy-based cache compression technique tailored for LLMs.Ecco combines group-wise and nonuniform quantization with pre-defined shared k-means patterns and Huffman coding to exploit the inherent entropy characteristics of LLM cache data.Recognizing the inefficiencies of traditional Huffman coding in terms of parallelism and latency, we introduce a novel parallel Huffman-based decoding process with a multi-stage pipeline design, reducing latency by two orders of magnitude and achieving throughput comparable to GPU L2 caches.Comprehensive evaluations demonstrate that Ecco achieves an up to 2.9× and 1.9× speedup over the state-of-the-art AWQ and SmoothQuant framework, 2.4× over the Olive accelerator, all while increasing memory capacity by nearly 4× and maintaining state-of-the-art LLM accuracy.These results underscore the effectiveness of our Cong Guo 0003, Chiyue Wei, Junyao Zhang 0003, Changchun Zhou 0001, Edward Hanson, Jiaqi Zhang 0002, Xiaoxiao Liu 0001, Hai Li 0001, Yiran Chen 0001 |
ISCA | 5 |
| 2024 | An Energy-Efficient Configurable Coprocessor Based on 1-D CNN for ECG Anomaly DetectionabstractMany healthcare devices have been widely used for electrocardiogram (ECG) monitoring. However, most of them have relatively low energy efficiency and lack flexibility. A novel ECG coprocessor is proposed in this paper, which can perform efficient ECG anomaly detection. In order to achieve high sensitivity and positive precision of R-peak detection, an algorithm based on Hilbert transform and adaptive threshold comparison is proposed. Also, a flexible one-dimensional convolutional neural network (1-D CNN) based classification engine is adopted, which can be configured with instructions to process various network models for different applications. Good energy efficiency is achieved by combining filter level parallelism and output channel parallelism within the processing element (PE) array with data reuse strategy. A 1-D CNN for arrhythmia detection is proposed to validate the hardware performance. The proposed ECG coprocessor is implemented using 55 nm CMOS technology, occupying an area of 1.39 mm2. At a clock frequency of 100MHz, the energy efficiency is 215.6 nJ/classification. The comparison results show that this design has advantages in energy overhead and detection performance. Chen Zhang 0031, QianXi Cheng, Changchun Zhou 0001, Xin'an Wang |
ISCAS | 4 |
| 2024 | SoftAct: A High-Precision Softmax Architecture for Transformers Supporting Nonlinear FunctionsabstractTransformer-based deep learning networks are revolutionizing our society. The convolution and attention co-designed (CAC) Transformers have demonstrated superior performance compared to the conventional Transformer-based networks. However, CAC Transformer networks contain various nonlinear functions, such as softmax and complex activation functions, which require high precision hardware design yet typically with significant cost in area and power consumption. To address these challenges,SoftAct, a compact and high-precision algorithm-hardware co-designed architecture, is proposed to implement both softmax and nonlinear activation functions in CAC Transformer accelerators. An improved softmax algorithm with penalties is proposed to maintain precision in hardware. A stage-wise full zero detection method is developed to skip redundant computation in softmax. A compact and reconfigurable architecture with a symmetrically designed linear fitting module is proposed to achieve nonlinear functions. TheSoftActarchitecture is designed in an industrial 28-nm CMOS technology with the MobileViT-xxs network classifying the ImageNet-1k dataset as the benchmark. Compared with the state of the art,SoftActimproves up to 5.87% network accuracy under 8-bit quantization, 153.2× area efficiency, and 1435× overall efficiency. Yuzhe Fu, Changchun Zhou 0001, Tianling Huang, Eryi Han, Yifan He 0002, Hailong Jiao |
IEEE Trans. Circuits Syst. Video Technol. | 2 |
| 2023 | An Energy-Efficient 3D Point Cloud Neural Network Accelerator With Efficient Filter Pruning, MLP Fusion, and Dual-Stream SamplingabstractThree-dimensional (3D) point cloud has been employed in a wide range of applications recently. As a powerful weapon for point cloud analysis, point-based point cloud neural networks (PNNs) have demonstrated superior performance with less computation complexity and parameters, compared to sparse 3D convolution-based networks and graph-based convolutional neural networks. However, point-based PNNs still suffer from high computational redundancy, large off-chip memory access, and low parallelism in hardware implementation, thereby hindering the applications on edge devices. In this paper, to address these challenges, an energy-efficient 3D point cloud neural network accelerator is proposed for on-chip edge computing. An efficient filter pruning scheme is used to skip the redundant convolution of pruned filters and zero-value feature channels. A block-wise multi-layer perceptron (MLP) fusion method is proposed to increase the on-chip reuse of features, thereby reducing off-chip memory access. A dual-stream blocking technique is proposed for higher parallelism while maintaining inference accuracy. Implemented in an industrial 28-nm CMOS technology, the proposed accelerator achieves an effective energy efficiency of 12.65 TOPS/W and 0.13 mJ/frame energy consumption for PointNeXt-S at 100 MHz, 0.9 V supply voltage, and 8-bit data width. Compared to the state-of-the-art point cloud neural network accelerators, the proposed accelerator enhances the energy efficiency by up to 66.6× and reduces the energy consumption per frame by up to 70.2×. Changchun Zhou 0001, Yuzhe Fu, Siyuan Qiu, Ge Li 0002, Yifan He 0002, Hailong Jiao |
ICCAD | 1 |
| 2023 | Sagitta: An Energy-Efficient Sparse 3D-CNN Accelerator for Real-Time 3-D UnderstandingabstractThree-dimensional (3-D) understanding or inference has received increasing attention, where 3-D convolutional neural networks (3D-CNNs) have demonstrated superior performance compared to 2D-CNNs, since 3D-CNNs learn features from all three dimensions. However, 3D-CNNs suffer from intensive computation and data movement. In this article, Sagitta, an energy-efficient low-latency on-chip 3D-CNN accelerator, is proposed for edge devices. Locality and small differential value dropout are leveraged to increase the sparsity of activations. A full-zero-skipping convolutional microarchitecture is proposed to fully utilize the sparsity of weights and activations. A hierarchical load-balancing scheme is also introduced to increase the hardware utilization. Specialized architecture and computation flow are proposed to enhance the effectiveness of the proposed techniques. Fabricated in a 55-nm CMOS technology, Sagitta achieves 3.8 TOPS/W for C3D at a latency of 0.1 s and 4.5 TOPS/W for 3D U-Net at a latency of 0.9 s at 100 MHz and 0.91-V supply voltage. Compared to the state-of-the-art 3D-CNN and 2D-CNN accelerators, Sagitta enhances the energy efficiency by up to$379.6\times $and$11\times $, respectively. Changchun Zhou 0001, Siyuan Qiu, Xugang Cao, Yuzhe Fu, Yifan He 0002, Hailong Jiao |
IEEE Internet Things J. | 1 |
| 2023 | CNN Accelerator at the Edge With Adaptive Zero Skipping and Sparsity-Driven Data FlowabstractAn energy-efficient convolutional neural network (CNN) accelerator is proposed for low-power inference on edge devices. An adaptive zero skipping technique is proposed to dynamically skip the zeros in either activations or weights, depending on which has the higher sparsity. The characteristic of non-zero data aggregation is explored to enhance the effectiveness of adaptive zero skipping in performance boosting. To mitigate the load imbalance issue after zero skipping, a sparsity-driven data flow and low-complexity dynamic task allocation are employed for different convolution layers. Facilitated further by a two-stage distiller, the proposed accelerator achieves$5.42\times $,$3.41\times $, and$3.42\times $performance boosting for VGG16, AlexNet, and Mobilenet-v1, respectively, compared to the baseline. Implemented in a 55-nm low power CMOS technology, the proposed accelerator achieves an effective energy efficiency of 2.41 TOPS/W, 2.35 TOPS/W, and 0.64 TOPS/W for VGG16, AlexNet, and Mobilenet-v1, respectively, at 100 MHz and 1.08 V supply voltage. Ming Liu 0022, Changchun Zhou 0001, Siyuan Qiu, Yifan He 0002, Hailong Jiao |
IEEE Trans. Circuits Syst. Video Technol. | 2 |
| 2021 | An Energy-Efficient Low-Latency 3D-CNN Accelerator Leveraging Temporal Locality, Full Zero-Skipping, and Hierarchical Load BalanceabstractThree-dimensional convolutional neural network (3D-CNN) has demonstrated outstanding classification performance in video recognition compared to two-dimensional CNN (2D-CNN), since 3D-CNN not only learns the spatial features of each frame, but also learns the temporal features across all frames. However, 3D-CNN suffers from intensive computation and data movement. To solve these issues, an energy-efficient low-latency 3D-CNN accelerator is proposed. Temporal locality and small differential value dropout are used to increase the sparsity of activation. Furthermore, to fully utilize the sparsity of weight and activation, a full zero-skipping convolutional microarchitecture is proposed. A hierarchical load-balancing scheme is also introduced to improve resource utilization. With the proposed techniques, a 3D-CNN accelerator is designed in a 55-nm low-power CMOS technology, bringing in up to 9.89× speedup compared to the baseline implementation. Benchmarked with C3D, the proposed accelerator achieves an energy efficiency of 4.66 TOPS/W at 100 MHz and 1.08 V supply voltage. Changchun Zhou 0001, Siyuan Qiu, Yifan He 0002, Hailong Jiao |
DAC | 1 |