Henry Leung

Prof. Dr. Henry Leung

Department of Electrical and Computer Engineering, University of Calgary, Calgary, AB T2N 1N4, Canada
orcid

Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 June 2019 in IEEE Sensors Journal
Verified
Journal Article
Closed access
ZHZhongyang Han
Zhongyang Han
JZJun Zhao
Jun Zhao
Henry LeungHenry Leung
Henry Leung
KMKing Fai Ma
King Fai Ma
WWWei Wang
Wei Wang
In order to approximate the underlying process of temporal data, time series prediction has been a hot research topic for decades. Developing predictive models plays an important role in interpreting complex real-world elements. With the sharp increase in the quantity and dimensionality of data, new challenges, such as extracting deep features, recognizing deep latent patterns have emerged, demanding novel approaches and effective solutions. Deep learning, composed of multiple processing layers to learn with multiple levels of abstraction, are now commonly deployed for overcoming the newly arisen difficulties. This paper reviews state-of-the-art developments in deep learning for time series prediction. Based on modeling for the perspective of conditional or joint probability, we categorize them into discriminative, generative and hybrids models. Experiments are implemented on both benchmarks and real-world data to elaborate the performance of representative deep learning-based prediction methods. Finally, we conclude with comments on possible future perspectives and ongoing challenges with time series prediction.

1 July 2020 in IEEE Transactions on Geoscience and Remote Sensing
Verified
Journal Article
Closed access
Peng WangPeng Wang
Peng Wang
Liguo WangLiguo Wang
Liguo Wang
Henry LeungHenry Leung
Henry Leung
GZGong Zhang
Gong Zhang
Due to the influences of imaging conditions, spectral imagery can be coarse and contain a large number of mixed pixels. These mixed pixels can lead to inaccuracies in the land-cover class (LC) mapping. Super-resolution mapping (SRM) can be used to analyze such mixed pixels and obtain the LC mapping information at the subpixel level. However, traditional SRM methods mostly rely on spatial correlation based on linear distance, which ignores the influences of nonlinear imaging conditions. In addition, spectral unmixing errors affect the accuracy of utilized spectral properties. In order to overcome the influence of linear and nonlinear imaging conditions and utilize more accurate spectral properties, the SRM based on spatial-spectral correlation (SSC) is proposed in this work. Spatial correlation is obtained using the mixed spatial attraction model (MSAM) based on the linear Euclidean distance. Besides, a spectral correlation that utilizes spectral properties based on the nonlinear Kullback-Leibler distance (KLD) is proposed. Spatial and spectral correlations are combined to reduce the influences of linear and nonlinear imaging conditions, which results in an improved mapping result. The utilized spectral properties are extracted directly by spectral imagery, thus avoiding the spectral unmixing errors. Experimental results on the three spectral images show that the proposed SSC yields better mapping results than state-of-the-art methods.

22 June 2024 in ACM Computing Surveys
Verified
Journal Article
Open access
JWJiajun Wu
Jiajun Wu
FDFan Dong
Fan Dong
Henry LeungHenry Leung
Henry Leung
Zhuangdi ZhuZhuangdi Zhu
Zhuangdi Zhu
JZJiayu Zhou
Jiayu Zhou
SDSteve Drew
Steve Drew
The ultra-low latency requirements of 5G/6G applications and privacy constraints call for distributed machine learning systems to be deployed at the edge. With its simple yet effective approach, federated learning (FL) is a natural solution for massive user-owned devices in edge computing with distributed and private training data. FL methods based on FedAvg typically follow a naive star topology, ignoring the heterogeneity and hierarchy of the volatile edge computing architectures and topologies in reality. Several other network topologies exist and can address the limitations and bottlenecks of the star topology. This motivates us to survey network topology-related FL solutions. In this paper, we conduct a comprehensive survey of the existing FL works focusing on network topologies. After a brief overview of FL and edge computing networks, we discuss various edge network topologies as well as their advantages and disadvantages. Lastly, we discuss the remaining challenges and future works for applying FL to topology-specific edge networks.

2 February 2021 in IEEE Transactions on Automatic Control
Verified
Journal Article
Closed access
HZHao Zhu
Hao Zhu
GZGuorui Zhang
Guorui Zhang
YLYongfu Li
Yongfu Li
Henry LeungHenry Leung
Henry Leung
In this article, a novel variational Bayesian (VB) adaptive Kalman filter with inaccurate nominal process and measurement noise covariances (PMNC) in the presence of outliers is proposed. The probability density functions of state transition and measurement likelihood are modeled as Gaussian–Gamma mixture distributions. The VB inference is used to perform the state and PMNC simultaneously. Simulations show that the effectiveness of the proposed method with inaccurate noise covariances in the presence of outliers environments.

11 April 2019 in IEEE Systems Journal
Verified
Journal Article
Closed access
HLHeng Li
Heng Li
SZShiYao Zhou
ShiYao Zhou
WYWei Yuan
Wei Yuan
JLJiahuan Li
Jiahuan Li
Henry LeungHenry Leung
Henry Leung
Recently, it was shown that the generative adversarial network (GAN) based adversarial-example attacks could thoroughly defeat the existing Android malware detection systems. However, they can be easily defended through deploying a firewall (i.e., adversarial example detector) to filter adversarial examples. To evade both malware detection and adversarial example detection, we develop a new adversarial-example attack method based on our proposed bi-objective GAN. Experiments show that over $\text{95\%}$ of adversarial examples generated by our method break through the firewall-equipped Android malware detection system, outperforming the state-of-the-art method by $\text{247.68\%}$ .

8 March 2019 in Sensors
Verified
Journal Article
Open access
PDF file
HZHao Zhu
Hao Zhu
BGBin Guo
Bin Guo
KZKe Zou
Ke Zou
YLYongfu Li
Yongfu Li
KYKa-Veng Yuen
Ka-Veng Yuen
Henry LeungHenry Leung
Henry Leung
This paper presents a comprehensive literature review on point set registration. The state-of-the-art modeling methods and algorithms for point set registration are discussed and summarized. Special attention is paid to methods for pairwise registration and groupwise registration. Some of the most prominent representative methods are selected to conduct qualitative and quantitative experiments. From the experiments we have conducted on 2D and 3D data, CPD-GL pairwise registration algorithm and JRMPC groupwise registration algorithm seem to outperform their rivals both in accuracy and computational complexity. Furthermore, future research directions and avenues in the area are identified.