Zhenni Li

Prof. Dr. Zhenni Li

School of Automation, Guangdong University of Technology, Guangzhou 510006, China

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

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

Representative Publications

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4 May 2020 in IEEE Transactions on Cybernetics
Verified
Journal Article
Closed access
ZYZuyuan Yang
Zuyuan Yang
NLNaiyao Liang
Naiyao Liang
WYWei Yan
Wei Yan
Zhenni LiZhenni Li
Zhenni Li
SXShengli Xie
Shengli Xie
Multiview data processing has attracted sustained attention as it can provide more information for clustering. To integrate this information, one often utilizes the non-negative matrix factorization (NMF) scheme which can reduce the data from different views into the subspace with the same dimension. Motivated by the clustering performance being affected by the distribution of the data in the learned subspace, a tri-factorization-based NMF model with an embedding matrix is proposed in this article. This model tends to generate decompositions with uniform distribution, such that the learned representations are more discriminative. As a result, the obtained consensus matrix can be a better representative of the multiview data in the subspace, leading to higher clustering performance. Also, a new lemma is proposed to provide the formulas about the partial derivation of the trace function with respect to an inner matrix, together with its theoretical proof. Based on this lemma, a gradient-based algorithm is developed to solve the proposed model, and its convergence and computational complexity are analyzed. Experiments on six real-world datasets are performed to show the advantages of the proposed algorithm, with comparison to the existing baseline methods.

4 February 2019 in IEEE Transactions on Industrial Informatics
Verified
Journal Article
Closed access
Zhenni LiZhenni Li
Zhenni Li
ZYZuyuan Yang
Zuyuan Yang
SXShengli Xie
Shengli Xie
Optimal computing resource allocation for edgecloud-assisted internet of things (IoT) in blockchain network is attracting increasing attention. Auction is a classical algorithm which guarantees that the computing resources are allocated to the buyers of the computing resource. However, the traditional auction algorithm only guarantees the revenue gains for the sellers of the computing resource. How to guarantee the seller and the buyer of the computing resource are both willing to trade and moreover bid truthfully is still open problem in computing resource trading for edge-cloud-assisted IoT. In this paper, we introduce a broker with the sparse information to manage and adjust the trading market. We then propose an iterative doublesided auction scheme for computing resource trading, where the broker solves an allocation problem to determine how much computing resource is traded and designs a specific price rule to induce the buyers and sellers of the computing resource to submit bids in a truthful way. Thus, the hidden information can be extracted gradually to obtain optimal computing resource allocation and trading prices. Hence, the proposed algorithm can achieve the maximum social welfare meanwhile protecting the privacies of the buyers and the sellers. Our theoretical analysis and simulations demonstrate that the proposed algorithm is efficient, i.e. achieving the maximum social welfare. In addition, the proposed algorithm can provide effective trading strategies for the buyers and sellers of the computing resource, leading to the proposed algorithm satisfying incentive compatibility, individual rationality, and budget balance.

18 May 2021 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
Minrui XuMinrui Xu
Minrui Xu
Jialiang PengJialiang Peng
Jialiang Peng
Brij GuptaBrij Gupta
Brij Gupta
JKJiawen Kang
Jiawen Kang
ZXZehui Xiong
Zehui Xiong
AEAhmed Abd El-Latif
Ahmed Abd El-Latif
Federated learning (FL) is an emerging technology for empowering various applications that generate large amounts of data in intelligent cyber–physical systems (ICPS). Though FL can address users’ concerns about data privacy, its maintenance still depends on efficient incentive mechanisms. For long-term incentivization to participants in data federation under dynamic environments, deep reinforcement learning as a promising technology has been extensively studied. However, the nonstationary problem caused by the heterogeneity of ICPS devices results in a serious effect on the convergence rate of existing single-agent reinforcement learning. In this article, we propose a multiagent learning-based incentive mechanism to capture the stationarity approximation in FL with heterogeneous ICPS. First, we formulate the secure communication and data resource allocation problem as a Stackelberg game in FL with multiple participants. Then, to tackle the heterogeneous problem, we model this multiagent game as a partially observable Markov decision process. In particular, a multiagent federated reinforcement learning algorithm is proposed to learn the allocation policies efficiently by dwindling variances in policy evaluation caused by interaction among multiple devices without the requirement of sharing privacy information. Moreover, the proposed algorithm is proved to attain convergence at an expected rate. Finally, extensive experimental results demonstrate that our proposed algorithm significantly outperforms baseline approaches.

14 August 2020 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
Zhenni LiZhenni Li
Zhenni Li
MXMinrui Xu
Minrui Xu
JNJiangtian Nie
Jiangtian Nie
JKJiawen Kang
Jiawen Kang
WCWuhui Chen
Wuhui Chen
SXShengli Xie
Shengli Xie
Blockchain technologies allow internet of things (IoT) to build trust among various interest parties. For the resource-limited IoT devices, offloading computation-intensive tasks (blockchain verification and mining tasks, data process tasks) to edge servers for execution is considered as a promising solution in mobile edge computing. However, conventional methods (such as linear programming or game theory) for computation offloading problem cannot achieve long-term performance while the existing deep reinforcement learning-based algorithms suffer from slow convergence, lack of robustness and unstable performance. In this paper, we propose a multi-agent deep reinforcement learning framework to achieve long-term performance for cooperative computation offloading, in which scatter network is adopted to improve its stability and league learning is introduced for agents to explore the environment collaboratively for fast convergence and robustness. First, we study the non-orthogonal multiple access-enabled cooperative computation offloading problem and formulate the joint problem as a Markov decision process by considering both the blockchain mining tasks and data processing tasks. Second, to avoid useless exploration and unstable performance, we initially train an intelligent agent represented by scatter networks using the conventional expert strategies. Third, in order to enhance the performance, we subsequently establish a hierarchical league where agents collaborate with others to explore the environment. Lastly, our experimental results demonstrate that our algorithm could perform better in terms of reducing energy cost and delay cost, and shortening almost 60% of the training time compared with the state-of-the-art approaches.

2 April 2019 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
Zhenni LiZhenni Li
Zhenni Li
ZYZuyuan Yang
Zuyuan Yang
SXShengli Xie
Shengli Xie
WCWuhui Chen
Wuhui Chen
KLKang Liu
Kang Liu
The introduction of edge computing into blockchain-enabled Internet of Things (IoT) for offloading computational tasks is attracting increasing attention. Computing resource trading unavoidably happens in edge-assisted IoT. However, efficient computing resource trading cannot be achieved because of the “cold start" and “long return" problems. To address these challenges, we propose to use a credit-based payment for fast computing resource trading in edge-assisted blockchain-enabled IoT; therefore, the IoT nodes can finish fast payment and frequent trading by borrowing resource coins from other IoT nodes based on their credit values. In our resource-coin loan problem, we propose an iterative double-auction-based algorithm, where a broker is introduced to solve the loan allocation problem and to determine the size of the loan each lender would provide to each borrower. Furthermore, the broker enforces specific loan pricing rules to induce the borrowers and lenders to bid truthfully. Then, the hidden privacy information could be extracted to achieve the optimal resource-coin allocation and loan pricing. The proposed algorithm can maximize the economic benefits while protecting privacy. Simulations showed that the proposed algorithm can maximize social welfare. In addition, we compared the proposed algorithm with the credit-bank-based method in terms of the satisfaction function and payments. The experimental results demonstrated that the proposed algorithm was individually rational, truthful and budget-balanced.

10 July 2019 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
KLKang Liu
Kang Liu
WCWuhui Chen
Wuhui Chen
ZZZibin Zheng
Zibin Zheng
Zhenni LiZhenni Li
Zhenni Li
WLWei Liang
Wei Liang
With the advancement and emergence of diverse network services in Internet of Vehicles (IoV), large volume of data are collected and stored, making data important properties. Data will be one of the most important commodities in the future blockchain-based IoV systems. However, efficiency challenges have been commonly found in blockchain-based data markets, which is mainly caused by transaction confirmation delays and the cold-start problems for new users. To address the efficiency challenges, we propose a secure, decentralized IoV data-trading system by exploiting the blockchain technology, and design an efficient debt-credit mechamism to support efficient data-trading in IoV. In the debt-credit mechanism, a vehicle with loan demand could loan from multi-vehicles by promising to pay interest and reward. In particular, we encourage loaning among vehicles by a motivation-based investing and pricing mechanism. We formulate a two-stage Stackelberg game to maximize the profits of borrower vehicle and lender vehicles jointly. In the first stage, the borrower vehicle set the interest rate and reward for the loan as its pricing strategies. In the second stage, the lender vehicles decide on their investing strategies. We apply backward induction to analyze the sub-game perfect equilibrium at each stage for both independent and uniform pricing schemes. We also validate the existence and uniqueness of Stackelberg equilibrium. The numerical results illustrate the efficiency of the proposed pricing schemes.