Video surveillance system is the integration of computers, networks, communications, and video CODEC, etc. Because of its distributed architecture, parallel image processing and ease of installation and expansion, it is widely used in many fields such as education, transportation and industry. However, there are some challenges of video surveillance applications in smart cities such as large scale of video events, low quality and big delay of video data transmission, and the loss of video surveillance data integrity. In order to solve the above problems, this paper designs a series of optimization algorithms and scheduling strategies based on Unmanned Aerial Vehicle (UAV) cluster. Firstly, we construct a full device coverage network with UAV cluster in heterogeneous communication environment of smart cities. Secondly, we formulate the scheduling problem of UAV cluster as bi-objective fragile bin packing problem, and design an optimal scheduling algorithm with constant approximation performance ratio. The simulation experimental results fully demonstrate the effectiveness, feasibility and robustness of the proposed solution in terms of system life cycle, video decodable frame rate, the ratio of UAV flight time to system life cycle, throughput and delay.
1 April 2024 in Digital Communications and Networks
Given a set of Disease surveillance Area (DsA)s and Point of disease Surveillance (PoS)s, some sensors are deployed to monitor these PoSs, and a drone collect data from the sensors as well as charge the sensors to extend their life-cycles. The drone replenish its energy by relying on the bus network. We first formulate the drone assisted regional disease surveillance problem under the constraints of life-cycle of sensors and energy of drone, and propose an approximation algorithm to find a feasible cycle of drone to minimize the traveling time cost of drone. To satisfy the diversity requirements and dynamic scalability of regional disease surveillance, we deploy one robot in each DsA instead of sensors. We further formulate the learning transferable driven regional disease surveillance problem, and propose a joint schedule algorithm of drone and robots. The results of both theoretical analysis and extensive simulations show that the proposed algorithms can reduce the total time cost by 39.71% and 48.74% and average waiting time by 42.00% and 50.14%, and increase the average accessing ratio of PoSs by 15.53% and 22.30%, through the assistance of bus network and learning transferable features.
2 October 2018 in Multimedia Tools and Applications
Operating system in intelligent transportation systems (ITSs) is a complex software system whose correctness and security are not obvious. There are advances in formal description and verification of operating systems in ITSs recently and they mainly focus on bottom-up proofs in which the source codes satisfy certain expected properties expressed by logic formulae. In this paper, we propose a layered object model for operating systems in ITSs. This model includes functionality layer, refinement layer and concrete layer. We consider the operating system object model as a logic system ( $L)$ with variables representing the objects of $L$ , and a series of logic formulae for security and functional configurations in security of ITSs. We establish a mathematical structure as a domain of discourse for operating system in ITSs and accordingly, construct a mapping from operating system objects to the domain. In this way, we propose a formal method to verify the operating system security properties and configurations in ITSs. We use the virtual memory management part of our self-designed operating system VSOS as an example to illustrate the model and show that the claimed security properties can be rigorously proven for ITSs. The evaluation and verification of VSOS indicate that the proposed model implementation is feasible and achieves the security goals.
1 April 2024 in Digital Communications and Networks