Jianhua Liu

Dr. Jianhua Liu


Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

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

Representative Publications

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11 July 2022 in IEEE Access
Verified
Journal Article
Open access
JLJianhua Liu
Jianhua Liu
ZWZibo Wu
Zibo Wu
JLJiajia Liu
Jiajia Liu
XTXiaoguang Tu
Xiaoguang Tu
Edge computing is a new computing paradigm which distributes tasks to edge networks for processing, it provides effective support for various mobile applications to meet their rapid response requirement. Unmanned Aerial Vehicle (UAV) has been widely used in emergency rescue, mapping, etc., with the advantages of flexible deployment and rapid movement. However, on one hand, mobile applications will be terminated when the battery energy is exhausted. On the other hand, mobile applications will be out of service when mobile devices are out of radio coverage of UAVs. How to achieve low-cost task unloading in the resource limited and location sensitive multi-UAVs edge computing environment is rather challenging. In this paper, we propose a distributed location-aware task offloading scheme, aiming at the above issues. Specifically, we create a nonlinear task allocation problem by combining the limited energy constraints of edge nodes with the random movement of users, where the cost function is divided into static and dynamic costs, respectively. Then, we formulate this problem to a convex optimization one with linear constrains, based on regularization technology. The mathematical proof shows that the scheme can support a parameterized competitive ratio without requiring any prior knowledge of the input task. The simulation results show that the proposed scheme can achieve lower cost edge computing services.

11 August 2025 in Sensors
Verified
Journal Article
Open access
PDF file
JLJiajia Liu
Jiajia Liu
HHHaoran Hu
Haoran Hu
XBXu Bai
Xu Bai
GLGuohua Li
Guohua Li
XZXudong Zhang
Xudong Zhang
JLJianhua Liu
Jianhua Liu
Unmanned Aerial Vehicles (UAVs) exhibit significant potential in enhancing the wireless communication coverage and service quality of Mobile Edge Computing (MEC) systems due to their superior flexibility and ease of deployment. However, the rapid growth of tasks leads to transmission queuing in edge networks, while the uneven distribution of user nodes and services causes network load imbalance, resulting in increased user waiting delays. To address these issues, we propose a multi-UAV collaborative MEC network model based on Non-Orthogonal Multiple Access (NOMA). In this model, UAVs are endowed with the capability to dynamically offload tasks among one another, thereby fostering a more equitable load distribution across the UAV swarm. Furthermore, the integration of NOMA is strategically employed to alleviating the inherent queuing delays in the communication infrastructure. Considering delay and energy consumption constraints, we formulate a task offloading strategy optimization problem with the objective of minimizing the overall system delay. To solve this problem, we design a delay-optimized offloading strategy based on the Twin Delayed Deep Deterministic Policy Gradient (TD3) algorithm. By jointly optimizing task offloading decisions and UAV flight trajectories, the system delay is significantly reduced. Simulation results show that, compared to traditional approaches, the proposed algorithm achieves a delay reduction of 20.2%, 9.8%, 17.0%, 12.7%, 15.0%, and 11.6% under different scenarios, including varying task volumes, the number of IoT devices, UAV flight speed, flight time, IoT device computing capacity, and UAV computing capability. These results demonstrate the effectiveness of the proposed solution and offloading decisions in reducing the overall system delay.

1 January 2024 in Computer Modeling in Engineering & Sciences
Verified
Journal Article
Open access
PDF file
JLJianhua Liu
Jianhua Liu
PXPeng Xie
Peng Xie
JLJiajia Liu
Jiajia Liu
XTXiaoguang Tu
Xiaoguang Tu
In mobile edge computing, unmanned aerial vehicles (UAVs) equipped with computing servers have emerged as a promising solution due to their exceptional attributes of high mobility, flexibility, rapid deployment, and terrain agnosticism. These attributes enable UAVs to reach designated areas, thereby addressing temporary computing swiftly in scenarios where ground-based servers are overloaded or unavailable. However, the inherent broadcast nature of line-of-sight transmission methods employed by UAVs renders them vulnerable to eavesdropping attacks. Meanwhile, there are often obstacles that affect flight safety in real UAV operation areas, and collisions between UAVs may also occur. To solve these problems, we propose an innovative A*SAC deep reinforcement learning algorithm, which seamlessly integrates the benefits of Soft Actor-Critic (SAC) and A* (A-Star) algorithms. This algorithm jointly optimizes the hovering position and task offloading proportion of the UAV through a task offloading function. Furthermore, our algorithm incorporates a path-planning function that identifies the most energy-efficient route for the UAV to reach its optimal hovering point. This approach not only reduces the flight energy consumption of the UAV but also lowers overall energy consumption, thereby optimizing system-level energy efficiency. Extensive simulation results demonstrate that, compared to other algorithms, our approach achieves superior system benefits. Specifically, it exhibits an average improvement of 13.18% in terms of different computing task sizes, 25.61% higher on average in terms of the power of electromagnetic wave interference intrusion into UAVs emitted by different auxiliary UAVs, and 35.78% higher on average in terms of the maximum computing frequency of different auxiliary UAVs. As for path planning, the simulation results indicate that our algorithm is capable of determining the optimal collision-avoidance path for each auxiliary UAV, enabling them to safely reach their designated endpoints in diverse obstacle-ridden environments.

26 July 2011 in Journal of Wuhan University of Technology-Mater. Sci. Ed.
Verified
Journal Article
Closed access
PDF file
JLJianhua Liu
Jianhua Liu
XHXuelong Hao
Xuelong Hao
SLSongmei Li
Songmei Li
MYMei Yu
Mei Yu

10 March 2026 in Pattern Recognition
Verified
Journal Article
Closed access
XTXiaoguang Tu
Xiaoguang Tu
ZGZeng Gao
Zeng Gao
LWLin Wei
Lin Wei
YZYanyan Zhang
Yanyan Zhang
JLJianhua Liu
Jianhua Liu
XLXuelong Li
Xuelong Li

16 September 2025 in Drones
Verified
Journal Article
Open access
PDF file
JLJianhua Liu
Jianhua Liu
XZXudong Zhang
Xudong Zhang
海周海涛 周
海涛 周
XLXia Lei
Xia Lei
HLHuiru Li
Huiru Li
XWXiaofan Wang
Xiaofan Wang
The demand for low-latency computing from the Internet of Things (IoT) and emerging applications challenges traditional cloud computing. Mobile Edge Computing (MEC) offers a solution by deploying resources at the network edge, yet terrestrial deployments face limitations. Unmanned Aerial Vehicles (UAVs), leveraging their high mobility and flexibility, provide dynamic computation offloading for User Equipments (UEs), especially in areas with poor infrastructure or network congestion. However, UAV-assisted MEC confronts significant challenges, including time-varying wireless channels and the inherent energy constraints of UAVs. We put forward the Lyapunov-based Deep Deterministic Policy Gradient (LyDDPG), a novel computation offloading algorithm. This algorithm innovatively integrates Lyapunov optimization with the Deep Deterministic Policy Gradient (DDPG) method. Lyapunov optimization transforms the long-term, stochastic energy minimization problem into a series of tractable, per-timeslot deterministic subproblems. Subsequently, DDPG is utilized to solve these subproblems by learning a model-free policy through environmental interaction. This policy maps system states to optimal continuous offloading and resource allocation decisions, aiming to minimize the Lyapunov-derived “drift-plus-penalty” term. The simulation outcomes indicate that, compared to several baseline and leading algorithms, the proposed LyDDPG algorithm reduces the total system energy consumption by at least 16% while simultaneously maintaining low task latency and ensuring system stability.