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Data offloading plays an important role for the mobile data explosion problem that occurs in cellular networks. This paper proposed an idea and control scheme for offloading vehicular communication traffic in the cellular network to vehicle to vehicle (V2V) paths that can exist in vehicular ad hoc networks (VANETs). A software-defined network (SDN) inside the mobile edge computing (MEC) architecture, which is abbreviated as the SDNi-MEC server, is devised in this paper to tackle the complicated issues of VANET V2V offloading. Using the proposed SDNi-MEC architecture, each vehicle reports its contextual information to the context database of the SDNi-MEC server, and the SDN controller of the SDNi-MEC server calculates whether there is a V2V path between the two vehicles that are currently communicating with each other through the cellular network. This proposed method: 1) uses each vehicle's context; 2) adopts a centralized management strategy for calculation and notification; and 3) tries to establish a VANET routing path for paired vehicles that are currently communicating with each other using a cellular network. The performance analysis for the proposed offloading control scheme based on the SDNi-MEC server architecture shows that it has better throughput in both the cellular networking link and the V2V paths when the vehicle's density is in the middle.

Using the non-equilibrium Green’s function and anti-bonding orbital model, a multiband treatment of quantum transport in an anisotropic semiconductor (Si-based) system is developed. In this study, we adopt Chiang’s boundary treatment of the open boundary system into the non-equilibrium Green’s function framework, and then an easy and powerful multiband treatment method is developed to solve the transmission coefficient of Si-based semiconductor quantum structures.

The bulk inversion asymmetry (Dresselhaus) terms (i.e., B2, B1, and B′1 terms) of wurtzite materials are determined. The 2 × 2 conduction band, 2 × 2 heavy-hole band, 2 × 2 light-hole band, and 2 × 2 crystal-field split-off hole band matrices of wurtzite semiconductors are developed and decoupled by using a block diagonal technique. Importantly, those 2 × 2 block diagonal matrices incorporate not only the interband coupling effect but also the bulk inversion asymmetry effect. Analytical expressions for the conduction and the valence band spin-splitting parameters and energies of GaN wurtzite materials are formulated by solving the block diagonal matrices. The presence of these terms is shown to include the spin-splitting phenomenon.