32 research outputs found
Pioneering Deterministic Scheduling and Network Structure Optimization for Time-Critical Computing Tasks in Industrial IoT
The Industrial Internet of Things (IIoT) has become a critical technology to
accelerate the process of digital and intelligent transformation of industries.
As the cooperative relationship between smart devices in IIoT becomes more
complex, getting deterministic responses of IIoT periodic time-critical
computing tasks becomes a crucial and nontrivial problem. However, few current
works in cloud/edge/fog computing focus on this problem. This paper is a
pioneer to explore the deterministic scheduling and network structural
optimization problems for IIoT periodic time-critical computing tasks. We first
formulate the two problems and derive theorems to help quickly identify
computation and network resource sharing conflicts. Based on this, we propose a
deterministic scheduling algorithm, \textit{IIoTBroker}, which realizes
deterministic response for each IIoT task by optimizing the fine-grained
computation and network resources allocations, and a network optimization
algorithm, \textit{IIoTDeployer}, providing a cost-effective structural upgrade
solution for existing IIoT networks. Our methods are illustrated to be
cost-friendly, scalable, and deterministic response guaranteed with low
computation cost from our simulation results.Comment: Under Revie
Deterministic Computing Power Networking: Architecture, Technologies and Prospects
With the development of new Internet services such as computation-intensive
and delay-sensitive tasks, the traditional "Best Effort" network transmission
mode has been greatly challenged. The network system is urgently required to
provide end-to-end transmission determinacy and computing determinacy for new
applications to ensure the safe and efficient operation of services. Based on
the research of the convergence of computing and networking, a new network
paradigm named deterministic computing power networking (Det-CPN) is proposed.
In this article, we firstly introduce the research advance of computing power
networking. And then the motivations and scenarios of Det-CPN are analyzed.
Following that, we present the system architecture, technological capabilities,
workflow as well as key technologies for Det-CPN. Finally, the challenges and
future trends of Det-CPN are analyzed and discussed
Collaborative Vehicular Edge Computing Networks: Architecture Design and Research Challenges
The emergence of augmented reality (AR), autonomous driving and other new applications have greatly enriched the functionality of the vehicular networks. However, these applications usually require complex calculations and large amounts of storage, which puts tremendous pressure on traditional vehicular networks. Mobile edge computing (MEC) is proposed as a prospective technique to extend computing and storage resources to the edge of the network. Combined with MEC, the computing and storage capabilities of the vehicular network can be further enhanced. Therefore, in this paper, we explore the novel collaborative vehicular edge computing network (CVECN) architecture. We first review the work related to MEC and vehicular networks. Then we discuss the design principles of CVECN. Based on the principles, we present the detailed CVECN architecture, and introduce the corresponding functional modules, communication process, as well as the installation and deployment ideas. Furthermore, the promising technical challenges, including collaborative coalition formation, collaborative task offloading and mobility management, are presented. And some potential research issues for future research are highlighted. Finally, simulation results are verified that the proposed CVECN can significantly improve network performance
In-plane Hall effect in rutile oxide films induced by the Lorentz force
The conventional Hall effect is linearly proportional to the field component
or magnetization component perpendicular to a film. Despite the increasing
theoretical proposals on the Hall effect to the in-plane field or magnetization
in various special systems induced by the Berry curvature, such an
unconventional Hall effect has only been experimentally reported in Weyl
semimetals and in a heterodimensional superlattice. Here, we report an
unambiguous experimental observation of the in-plane Hall effect (IPHE) in
centrosymmetric rutile RuO2 and IrO2 single-crystal films under an in-plane
magnetic field. The measured Hall resistivity is found to be proportional to
the component of the applied in-plane magnetic field along a particular crystal
axis and to be independent of the current direction or temperature. Both the
experimental observations and theoretical calculations confirm that the IPHE in
rutile oxide films is induced by the Lorentz force. Our findings can be
generalized to ferromagnetic materials for the discovery of in-plane anomalous
Hall effects and quantum anomalous Hall effects. In addition to significantly
expanding knowledge of the Hall effect, this work opens the door to explore new
members in the Hall effect family
Controlled Synthesis and Selective Adsorption Properties of Pr2CuO4 Nanosheets: a Discussion of Mechanism
Abstract Tetragonal-phase Pr2CuO4 nanosheets with a thickness of about 60 nm were synthesized using the coordination compound methods (CCMs), then used as highly efficient selective adsorbent towards malachite green (MG) in aqueous solutions. The Pr2CuO4 samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectrum (DRS), and standard Brunauer–Emmett–Teller (BET) methods. The maximum adsorption capacity (Q m ) of as-prepared samples was determined by adsorption isotherms with different adsorbent doses (m) of 0.03–0.07 g at 298, 318, and 338 K based on the Langmuir model. When m  0.07 g, effects of systemic mass loss and particle aggregation were discussed on the data deviation from the Langmuir model at 298 K. Based on the hydrogen bond and coordination bond, a possible mechanism of selective adsorption of MG by Pr2CuO4 is proposed, which was further verified by the adsorption experiments of CuO and Pr2O3 towards MG and competing-ion experiments. Finally, the theoretic studies were performed at DFT level to reveal the possible adsorption process
Resource allocation and user association for HTTP adaptive streaming in heterogeneous cellular networks with small cells
Video streaming, especially hypertext transfer protocol based (HTTP) adaptive streaming (HAS) of video, has been expected to be a dominant application over mobile networks in the near future, which brings huge challenge for the mobile networks. Although some works have been done for video streaming delivery in heterogeneous cellular networks, most of them focus on the video streaming scheduling or the caching strategy design. The problem of joint user association and rate allocation to maximize the system utility while satisfying the requirement of the quality of experience of users is largely ignored. In this paper, the problem of joint user association and rate allocation for HTTP adaptive streaming in heterogeneous cellular networks is studied, we model the optimization problem as a mixed integer programming problem. And to reduce the computational complexity, an optimal rate allocation using the Lagrangian dual method under the assumption of knowing user association for BSs is first solved. Then we use the many-to-one matching model to analyze the user association problem, and the joint user association and rate allocation based on the distributed greedy matching algorithm is proposed. Finally, extensive simulation results are illustrated to demonstrate the performance of the proposed scheme
Quantitative Estimation of Pipeline Slope Disaster Risk in China
Abstract China’s economic development is closely related to oil and gas resources, and the country is investing heavily in pipeline construction. Slope geological hazards seriously affect the long-term safe operation of buried pipelines, usually causing pipeline leakage, property and environmental losses, and adverse social impacts. To ensure the safety of pipelines and reduce the probability of pipeline disasters, it is necessary to predict and quantitatively evaluate slope hazards. While there has been much research focus in recent years on the evaluation of pipeline slope disasters and the stress calculation of pipelines under hazards, existing methods only provide information on the occurrence probability of slope events, not whether a slope disaster will lead to pipeline damage. Taking the 2015 Xinzhan landslide in Guizhou Province, China, as an example, this study used discrete elements to simulate landslide events and determine the risk level and scope for pipeline damage, and then established a pipe-soil coupling model to quantitatively evaluate the impact of landslide hazards for pipelines in medium- and high-risk areas. The results provide a reference for future pipeline disaster prevention and control