VLDB 2026 Research / reviewers in the wild / expert
Zhang Liu 0001
dblp:01/8024-1
· DBLP profile ↗
10ranked-venue papers
6as first author
10since 2021 · last 2026
0000-0003-2310-661XORCID · conflict
Domains — the database's venue-derived domains; a paper can count in several
Computer networks · 8 · 5 first-author · 8 since 2021Graphics, computer vision, multimedia, augmented reality and games · 1 · 1 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | Two-Timescale Model Caching and Resource Allocation for Edge-Enabled AI-Generated Content ServicesabstractGenerative AI (GenAI) has emerged as a transformative technology, enabling customized and personalized AI-generated content (AIGC) services. In this paper, we address challenges of edge-enabled AIGC service provisioning, which remain underexplored in the literature. These services require executing GenAI models with billions of parameters, posing significant obstacles to resource-limited wireless edge. We subsequently introduce the formulation of joint model caching and resource allocation for AIGC services to balance a trade-off between AIGC quality and latency metrics. We obtain mathematical relationships of these metrics with the computational resources required by GenAI models via experimentation. Afterward, we decompose the formulation into a model caching subproblem on a long-timescale and a resource allocation subproblem on a short-timescale. Since the variables to be solved are discrete and continuous, respectively, we leverage a double deep Q-network (DDQN) algorithm to solve the former subproblem and propose a diffusion-based deep deterministic policy gradient (D3PG) algorithm to solve the latter. The proposed D3PG algorithm makes an innovative use of diffusion models as the actor network to determine optimal resource allocation decisions. Consequently, we integrate these two learning methods within the overarching two-timescale deep reinforcement learning (T2DRL) algorithm, the performance of which is studied through comparative numerical simulations. Zhang Liu 0001, Hongyang Du 0001, Xiangwang Hou, Lianfen Huang, Seyyedali Hosseinalipour, Dusit Niyato, Khaled Ben Letaief |
IEEE Trans. Mob. Comput. | 1 |
| 2026 | Task Assignment and Exploration Optimization for Low Altitude UAV Rescue via Generative AI Enhanced Multi-Agent Reinforcement LearningabstractThe integration of emerging uncrewed aerial vehicle (UAV) with artificial intelligence (AI) and ground-embedded robots (GERs) has transformed emergency rescue operations in unknown environments. However, the high computational demands of such missions often exceed the capacity of a single UAV, making it difficult for the system to continuously and stably provide high-level services. To address these challenges, this paper proposes a novel cooperation framework involving UAVs, GERs, and airships. This framework enables resource pooling through UAV-to-GER (U2G) and UAV-to-airship (U2A) communications, providing computing services for UAV offloaded tasks. Specifically, we formulate the multi-objective optimization problem of task assignment and exploration optimization in UAVs as a dynamic long-term optimization problem. Our objective is to minimize task completion time and energy consumption while ensuring system stability over time. To achieve this, we first employ the Lyapunov optimization method to transform the original problem, with stability constraints, into a per-slot deterministic problem. We then propose an algorithm named HG-MADDPG, which combines the Hungarian algorithm with a generative diffusion model (GDM)-based multi-agent deep deterministic policy gradient (MADDPG) approach, to jointly optimize exploration and task assignment decisions. In HG-MADDPG, we first introduce the Hungarian algorithm as a method for exploration area selection, enhancing UAV efficiency in interacting with the environment. We then innovatively integrate the GDM and multi-agent deep deterministic policy gradient (MADDPG) to optimize task assignment decisions, such as task offloading and resource allocation. Simulation results demonstrate the effectiveness of the proposed approach, with significant improvements in task offloading efficiency, latency reduction, and system stability compared to baseline methods. Qian Chen 0019, Wenjie Weng, Zhang Liu 0001, Jiacheng Wang 0001, Geng Sun 0001, Xiaohuan Li 0001, Dusit Niyato |
IEEE Trans. Mob. Comput. | 5 |
| 2026 | A Lyapunov-Guided Diffusion-Based Reinforcement Learning Approach for UAV-Assisted Vehicular Networks With Delayed CSI FeedbackabstractLow altitude uncrewed aerial vehicles (UAVs) are expected to facilitate the development of aerial-ground integrated intelligent transportation systems and unlocking the potential of the emerging low-altitude economy. However, several critical challenges persist, including the dynamic optimization of network resources and UAV trajectories, limited UAV endurance, and imperfect channel state information (CSI). In this paper, we offer new insights into low-altitude economy networking by exploring intelligent UAV-assisted vehicle-to-everything communication strategies aligned with UAV energy efficiency. Particularly, we formulate an optimization problem of joint channel allocation, power control, and flight altitude adjustment in UAV-assisted vehicular networks. Taking CSI feedback delay into account, our objective is to maximize the vehicle-to-UAV communication sum rate while satisfying the UAV's long-term energy constraint. To this end, we first leverage Lyapunov optimization to decompose the original long-term problem into a series of per-slot deterministic subproblems. We then propose a diffusion-based deep deterministic policy gradient (D3PG) algorithm, which innovatively integrates diffusion models to determine optimal channel allocation, power control, and flight altitude adjustment decisions. Through extensive simulations using real-world vehicle mobility traces, we demonstrate the superior performance of the proposed D3PG algorithm compared to existing benchmark solutions. Zhang Liu 0001, Lianfen Huang, Zhibin Gao, Xianbin Wang 0001, Dusit Niyato, Xuemin Shen |
IEEE Trans. Wirel. Commun. | 1 |
| 2025 | Joint Model Caching and Resource Allocation in Generative AI - Enabled Wireless Edge NetworksabstractWith the rapid advancement of artificial intelligence (AI), generative AI (GenAI) has emerged as a transformative tool, enabling customized and personalized AI-generated content (AIGC) services. However, GenAI models with billions of parameters require substantial memory capacity and computational power for deployment and execution, presenting significant challenges to resource-limited edge networks. In this paper, we address the joint model caching and resource allocation problem in GenAI-enabled wireless edge networks. Our objective is to balance the trade-off between delivering high-quality AIGC and minimizing the delay in AI GC service provisioning. To tackle this problem, we employ a deep deterministic policy gradient (DDPG)-based reinforcement learning approach, capable of efficiently determining optimal model caching and resource allocation decisions for AIGC services in response to user mobility and time-varying channel conditions. Numerical results demonstrate that DDPG achieves a higher model hit ratio and provides superior-quality, lower-latency AIGC services compared to other benchmark solutions. Zhang Liu 0001, Hongyang Du 0001, Lianfen Huang, Zhibin Gao, Dusit Niyato |
WCNC | 1 |
| 2025 | DNN Partitioning, Task Offloading, and Resource Allocation in Dynamic Vehicular Networks: A Lyapunov-Guided Diffusion-Based Reinforcement Learning ApproachabstractThe rapid advancement of Artificial Intelligence (AI) has introduced Deep Neural Network (DNN)-based tasks to the ecosystem of vehicular networks. These tasks are often computation-intensive, requiring substantial computation resources, which are beyond the capability of a single vehicle. To address this challenge, Vehicular Edge Computing (VEC) has emerged as a solution, offering computing services for DNN-based tasks through resource pooling via Vehicle-to-Vehicle/Infrastructure (V2V/V2I) communications. In this paper, we formulate the problem of joint DNN partitioning, task offloading, and resource allocation in VEC as a dynamic long-term optimization. Our objective is to minimize the DNN-based task completion time while guaranteeing the system stability over time. To this end, we first leverage a Lyapunov optimization technique to decouple the original long-term optimization with stability constraints into a per-slot deterministic problem. Afterwards, we propose a Multi-Agent Diffusion-based Deep Reinforcement Learning (MAD2RL) algorithm, incorporating the innovative use of diffusion models to determine the optimal DNN partitioning and task offloading decisions. Furthermore, we integrate convex optimization techniques into MAD2RL as a subroutine to allocate computation resources, enhancing the learning efficiency. Through simulations under real-world movement traces of vehicles, we demonstrate the superior performance of our proposed algorithm compared to existing benchmark solutions. Zhang Liu 0001, Hongyang Du 0001, Junzhe Lin, Zhibin Gao, Lianfen Huang, Seyyedali Hosseinalipour, Dusit Niyato |
IEEE Trans. Mob. Comput. | 1 |
| 2024 | Collaborative Sensing-Assisted Task Offloading and Resource Allocation for ISAC-Based Vehicular CloudsabstractWith the rapid development of vehicular networks, ever-growing number of on-board sensors makes vehicle applications/tasks to be not only computation-intensive but also data-intensive. To this end, Vehicular Cloud Computing (VCC) has been convinced as a promising paradigm to offer valuable computing and sensing services to vehicles. However, considering the heterogeneity of on-board computation and sensing capabilities, how to efficiently determine the appropriate vehicle to process the task is challenging. Also, the allocation of transmission power can significantly impact the corresponding energy consumption. Therefore, to minimize the weighted sum of execution delay and energy consumption of vehicle tasks, in this paper, we propose a Collaborative Sensing-Assisted Task Offloading and Resource Al-location (CSTR) algorithm based on the Integrated Sensing and Communication (ISAC) mechanism. The optimization problem is formulated as a mixed integer nonlinear programming problem (MINLP), which is proven to be NP-hard. To achieve this, the original problem is decoupled into two sub-problems namely the task offloading problem and transmission power allocation problem, which are solved by Genetic Algorithm (GA) and convex optimization technique, respectively. Validation through several simulations based on real-world road networks has demonstrated that our proposed CSTR can outperform existing benchmark solutions under various settings. Junzhe Lin, Zhang Liu 0001, Ning Chen 0011, Lianfen Huang |
VTC Spring | 2 |
| 2024 | A Lyapunov-Based Resource Allocation Method for Edge-Assisted Industrial Internet of ThingsabstractIn edge computing-enhanced industrial Internet of Things (IIoT) environments, networks with multiple terminal equipments (TEs) and edge servers (ESs) face significant challenges in energy-efficient task offloading and resource allocation due to dynamic computational demands and uncertain energy supply. We propose a novel system framework that organizes computation tasks and energy into queues for each TE, allowing TEs to acquire energy and offload tasks to adjacent ESs. This framework optimizes key variables, such as transmission power, CPU processing speeds, and data volume to reduce latency and improve energy efficiency. Additionally, we introduce a Lyapunov optimization-based coalition game approach for computation offloading and resource allocation. This method effectively addresses the coupled and nonconvex optimization challenge by ensuring the system stability and efficiently balancing delay and energy consumption. Comprehensive simulation experiments have shown that this algorithm significantly reduces the cost of ES-Assisted IIoT systems and improves the system performance. Jieyi Zhang 0002, Yongzhi Zhai, Zhang Liu 0001 |
IEEE Internet Things J. | 3 |
| 2024 | GA-DRL: Graph Neural Network-Augmented Deep Reinforcement Learning for DAG Task Scheduling Over Dynamic Vehicular CloudsabstractVehicular Clouds (VCs) are modern platforms for processing of computation-intensive tasks over vehicles. Such tasks are often represented as Directed Acyclic Graphs (DAGs) consisting of interdependent vertices/subtasks and directed edges. However, efficient scheduling of DAG tasks over VCs presents significant challenges, mainly due to the dynamic service provisioning of vehicles within VCs and non-Euclidean representation of DAG tasks’ topologies. In this paper, we propose a Graph neural network-Augmented Deep Reinforcement Learning scheme (GA-DRL) for the timely scheduling of DAG tasks over dynamic VCs. In doing so, we first model the VC-assisted DAG task scheduling as a Markov decision process. We then adopt a multi-head Graph ATtention network (GAT) to extract the features of DAG subtasks. Our developed GAT enables a two-way aggregation of the topological information in a DAG task by simultaneously considering predecessors and successors of each subtask. We further introduce non-uniform DAG neighborhood sampling through codifying the scheduling priority of different subtasks, which makes our developed GAT generalizable to completely unseen DAG task topologies. Finally, we augment GAT into a double deep Q-network learning module to conduct subtask-to-vehicle assignment according to the extracted features of subtasks, while considering the dynamics and heterogeneity of the vehicles in VCs. Through simulating various DAG tasks under real-world movement traces of vehicles, we demonstrate that GA-DRL outperforms existing benchmarks in terms of DAG task completion time. Zhang Liu 0001, Lianfen Huang, Zhibin Gao, Manman Luo, Seyyedali Hosseinalipour, Huaiyu Dai |
IEEE Trans. Netw. Serv. Manag. | 1 |
| 2024 | Integrated Sensing, Communication, and Computing for Cost-effective Multimodal Federated PerceptionabstractFederated learning (FL) is a prominent paradigm of 6G edge intelligence (EI), which mitigates privacy breaches and high communication pressure caused by conventional centralized model training in the artificial intelligence of things (AIoT). The execution of multimodal federated perception (MFP) services comprises three sub-processes, including sensing-based multimodal data generation, communication-based model transmission, and computing-based model training, ultimately competitive on available underlying multi-domain physical resources such as time, frequency, and computing power. How to reasonably coordinate the multi-domain resources scheduling among sensing, communication, and computing, therefore, is vital to the MFP networks. To address the above issues, this article explores service-oriented resource management with integrated sensing, communication, and computing (ISCC). Specifically, employing the incentive mechanism of the MFP service market, the resources management problem is defined as a social welfare maximization problem, where the concept of “expanding resources” and “reducing costs” is used to enhance learning performance gain and reduce resource costs. Experimental results demonstrate the effectiveness and robustness of the proposed resource scheduling mechanisms. Ning Chen 0012, Zhipeng Cheng, Xuwei Fan, Zhang Liu 0001, Bangzhen Huang, Lianfen Huang, Xiaojiang Du, Mohsen Guizani |
ACM Trans. Multim. Comput. Commun. Appl. | 4 |
| 2021 | Topology-Aware Dynamic Computation Offloading in Vehicular NetworksabstractDriven by the tremendous in vehicular networks computation-intensive application demands, the incorporation of mobile edge computing (MEC) and vehicular cloud is convinced as a promising paradigm to fulfill computation offloading requirements. However, the changing vehicular communication topology (CVCT) poses a significant challenge for offloading directed acyclic graph (DAG) model application. Due to the precedence and connection constraint between different sub-jobs, the successful offloading of DAG-enabled apllication will be disturbed even interrupted without considering CVCT. To address this problem, we propose a topology-aware dynamic computaion offloading mechanism and adopt simulated annealing algorithm (TASA) to jointly optimize the energy consumption and completion time under dynamic environment, while guaranteeing the convergence of the proposed method. Simulation results reveal the effectiveness of the proposed method in overcoming CVCT’s influence. Zhang Liu 0001, Zhibin Gao, Minghui LiWang, Fangzhe Chen, Lianfen Huang, Yuliang Tang |
VTC Spring | 1 |