A Low-Cost Resource Re-Allocation Scheme for Increasing the Number of Guaranteed Services in Resource-Limited Vehicular Networks

Abstract

Vehicular networks are becoming increasingly dense due to expanding wireless services and platooning has been regarded as a promising technology to improve road capacity and on-road safety. Constrained by limited resources, not all communication links in platoons can be allocated to the resources without suffering interference. To guarantee the quality of service, it is required to determine the set of served services at which the scale of demand exceeds the capability of the network. To increase the number of guaranteed services, the resource allocation has to be adjusted to adapt to the dynamic environment of the vehicular network. However, resource re-allocation results in additional costs, including signal overhead and latency. To increase the number of guaranteed services at a low-cost in a resource-limited vehicular network, we propose a time dynamic optimization method that constrains the network re-allocation rate. To decrease the computational complexity, the time dynamic optimization problem is converted into a deterministic optimization problem using the Lyapunov optimization theory. The simulation indicates that the analytical results do approximate the reality, and that the proposed scheme results in a higher number of guaranteed services as compared to the results of a similar algorithm.

Natural eutectogels: sustainable catalytic systems for C–C bond formation reactions

“…This explains the surge in interest that, in the last few years, has promoted the employment of transition metal free protocols, 1 supported catalysts 2 and photochemical processes. [3][4][5] Among different perspectives, also the possibility to perform these reactions in confined and highly organised media has recently gained attention. Consequently, the use of zeolites, 6,7 covalent organic frameworks, 8,9 and metal organic frameworks 10,11 has been promoted.…”

Modern metal-catalyzed and organocatalytic methods for synthesis of coumarin derivatives: a review

“…18, 107) gave two regioisomers 108 and 109 with a ratio of 1 : 0.65. 85 Another very similar ruthenium-catalyzed method was reported in 2018 by Chao Jiang and his group with ruthenium complexes as photocatalysts (Scheme 28). 86 In this protocol, phenyl propiolate 110 was coupled with aliphatic or aromatic aldehyde 111 in the presence of Ru(bpy) 3 Cl 2 as the photocatalyst, TBHP 96 as oxidant, K 2 HPO 4 as the base, and MeCN as solvent under a nitrogen atmosphere at ambient temperature and under visible light to produce 3-acylcoumarins 112.…”

“…A visible-light-promoted ruthenium-catalyzed radical method for synthesizing 3-functionalized coumarin derivatives 102 was reported by Weiwei Zhang's research group in 2016 (Scheme 27). 85 The group coupled aro-matic ethers 101 (important to have α-hydrogen) with alkynoates 100 in the presence of Ru(bpy) 3 Cl 2 as the photoredox catalyst, TBHP (tert-butyl hydroperoxide) 96 as oxidant, and CH 3 CN as the solvent in an argon atmosphere under 34 W blue LED at ambient temperature.…”

A Survey on Resource Allocation in Vehicular Networks

“…Moreover, to obtain a stable platoon, a formation algorithm was proposed in [61] based on a leader evaluation method. Authors in [62] presented a RA strategy to reduce the re-allocation rate that enhances the number of guaranteed services in vehicle platooning network. A time dynamic optimization problem was formulated in [62] under the constraint of a network re-allocation rate.…”

“…Authors in [62] presented a RA strategy to reduce the re-allocation rate that enhances the number of guaranteed services in vehicle platooning network. A time dynamic optimization problem was formulated in [62] under the constraint of a network re-allocation rate. To further reduce the computational complexity, their proposed optimization problem was converted into a deterministic optimization problem using the Lyapunov optimization theory [9].…”