Pu Tian

Dr. Pu Tian


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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13 May 2022 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
PTPu Tian
Pu Tian
Weixian LiaoWeixian Liao
Weixian Liao
Wei YuWei Yu
Wei Yu
Erik BlaschErik Blasch
Erik Blasch
The fast development of the Internet of Things (IoT) and deep learning enables learning useful patterns from the massive amount of collected data with sporadic nodes in IoT systems. Federated learning has received increasing attention in distributed machine learning where only intermediate parameters are exchanged with training samples that resided at local nodes. Nonetheless, most of the existing federated learning schemes assume a homogeneous distribution of data. The assumption, however, does not apply to IoT systems because of the heterogeneity of the IoT architecture. The nonindependent and identical distribution (non-IID) property in data volume and statistical distribution of IoT nodes can impact the performance of an aggregated global model that fits all nodes. Existing federated learning solutions for non-IID data sets either have to train additional models or require extra data exchange to check the node distribution. However, due to resource constraints in IoT systems, these approaches will increase the burden on limited computation capacity and cause network overhead. To address the issue, in this article, a novel weight-similarity-based client clustering (WSCC) approach is proposed, in which clients are split into different groups based on their data set distributions. An affinity-propagation-based method with the cosine distance of the client’s weight parameters is designed to iteratively and automatically determine dynamic clusters. The proposed approach is ideal for IoT systems since there are no auxiliary models and extra data transmissions are needed. Through the theoretical convergence analysis and empirical results, we show that our proposed WSCC scheme outperforms the representative federated learning schemes under different non-IID settings, achieving up to 20% improvements in accuracy.

16 June 2020 in IEEE Transactions on Network Science and Engineering
Verified
Journal Article
Closed access
ZCZheyi Chen
Zheyi Chen
PTPu Tian
Pu Tian
Weixian LiaoWeixian Liao
Weixian Liao
Wei YuWei Yu
Wei Yu
The simultaneous development of deep learning techniques and Internet of Things (IoT)/Cyber-physical Systems (CPS) technologies has afforded untold possibilities for improving distributed computing, sensing, and data analysis. Among these technologies, federated learning has received increased attention as a privacy-preserving collaborative learning paradigm, and has shown significant potential in IoT/CPS-driven large-scale smart-world systems. At the same time, the vulnerabilities of deep neural networks, especially to adversarial attacks, cannot be overstated and should not be minimized. Moreover, distributed nature of federated learning makes defense against such adversarial attacks a more challenging problem due to unavailability of local data and resource heterogeneity. To tackle these challenges, in this paper, we propose ZeKoC, a Zero Knowledge Clustering approach to mitigate adversarial attacks. Particularly, we first formulate the problem of resource-constrained adversarial mitigation. Specifically, noting that global server has no access to training samples, we reformulate the unsupervised weight clustering problem. Our proposed ZeKoC approach allows the server to automatically split and merge weight clusters for weight selection and aggregation. Theoretical analysis of our approach demonstrates that convergence is guaranteed. Our experimental results illustrate that, in a non-i.i.d. (i.e., independent-and-identically distributed) data setting, our ZeKoC approach can successfully mitigate general attacks while outperforming state-of-art schemes.

29 June 2024 in Future Internet
Verified
Journal Article
Open access
PDF file
MQMian Qian
Mian Qian
CQCheng Qian
Cheng Qian
GXGuobin Xu
Guobin Xu
PTPu Tian
Pu Tian
Wei YuWei Yu
Wei Yu
Irrigation refers to supplying water to soil through pipes, pumps, and spraying systems to ensure even distribution across the field. In traditional farming or gardening, the setup and usage of an agricultural irrigation system solely rely on the personal experience of farmers. The Food and Agriculture Organization of the United Nations (UN) has projected that by 2030, developing countries will expand their irrigated areas by 34%, while water consumption will only be up 14%. This discrepancy highlights the importance of accurately monitoring water flow and volume rather than people’s rough estimations. The smart irrigation systems, a key subsystem of smart agriculture known as the cyber–physical system (CPS) in the agriculture domain, automate the administration of water flow, volume, and timing via using cutting-edge technologies, especially the Internet of Things (IoT) technology, to solve the challenges. This study explores a comprehensive three-dimensional problem space to thoroughly analyze the IoT’s applications in irrigation systems. Our framework encompasses several critical domains in smart irrigation systems. These domains include soil science, sensor technology, communication protocols, data analysis techniques, and the practical implementations of automated irrigation systems, such as remote monitoring, autonomous operation, and intelligent decision-making processes. Finally, we discuss a few challenges and outline future research directions in this promising field.

31 March 2023 in IEEE Transactions on Emerging Topics in Computing
Verified
Journal Article
Closed access
ZCZheyi Chen
Zheyi Chen
PTPu Tian
Pu Tian
Weixian LiaoWeixian Liao
Weixian Liao
XCXuhui Chen
Xuhui Chen
GXGuobin Xu
Guobin Xu
Wei YuWei Yu
Wei Yu
The rise of deep learning and the Internet of Things (IoT) has driven a number of smart-world applications, which are mostly deployed in distributed environments. Federated learning, a privacy-preserving collaborative learning paradigm, has shown considerable potential to leverage the rich distributed data at network edges. Nonetheless, the heterogeneity of IoT devices and their connected network environment impedes federated learning applications in IoT systems. Particularly, the stale gradients updated by slower local learners impact the effectiveness of federated learning. Transmitting weight updates with a large number of users leads to network congestion at the edge of the network and incurs unaffordable communication costs. To overcome these challenges, we propose a transfer knowledge based federated learning framework under a resource-limited distributed system. We formulate a knowledge distillation based federated learning optimization problem with the consideration of dynamic local resource. The proposed approach carries out federated learning with the help of knowledge distillation to avoid occupying the expensive network bandwidth or bringing a heavy burden to the network. Theoretical analysis demonstrates convergence of the learning process. The experimental results on three public datasets illustrate that the proposed framework is capable of substantially improving the efficiency of federated learning and outperforming state-of-the-art schemes.

1 June 2021 in High-Confidence Computing
Verified
Journal Article
Open access
ZCZheyi Chen
Zheyi Chen
PTPu Tian
Pu Tian
Weixian LiaoWeixian Liao
Weixian Liao
Wei YuWei Yu
Wei Yu

30 April 2022 in Future Internet
Verified
Journal Article
Open access
PDF file
ZCZheyi Chen
Zheyi Chen
Weixian LiaoWeixian Liao
Weixian Liao
PTPu Tian
Pu Tian
Qianlong WangQianlong Wang
Qianlong Wang
Wei YuWei Yu
Wei Yu
Distributed machine learning paradigms have benefited from the concurrent advancement of deep learning and the Internet of Things (IoT), among which federated learning is one of the most promising frameworks, where a central server collaborates with local learners to train a global model. The inherent heterogeneity of IoT devices, i.e., non-independent and identically distributed (non-i.i.d.) data, and the inconsistent communication network environment results in the bottleneck of a degraded learning performance and slow convergence. Moreover, most weight averaging-based model aggregation schemes raise learning fairness concerns. In this paper, we propose a peer-to-peer decentralized learning framework to tackle the above issues. Particularly, each local client iteratively finds a learning pair to exchange the local learning model. By doing this, multiple learning objectives are optimized to advocate for learning fairness while avoiding small-group domination. The proposed fairness-aware approach allows local clients to adaptively aggregate the received model based on the local learning performance. The experimental results demonstrate that the proposed approach is capable of significantly improving the efficacy of federated learning and outperforms the state-of-the-art schemes under real-world scenarios, including balanced-i.i.d., unbalanced-i.i.d., balanced-non.i.i.d., and unbalanced-non.i.i.d. environments.