Fog-radio access networks (F-RANs) alleviate fronthaul delays for cellular networks as compared to their cloud counterparts. This allows them to be suitable solutions for networks that demand low propagation delays. Namely, they are suitable for millimeter wave (mmWave) operations that suffer from short propagation distances and possess a poor scattering environment (low channel ranks). The F-RAN here is comprised of fog nodes that are collocated with radio remote heads (RRHs) to provide local processing capabilities for mobile station (MS) terminals. These terminals demand various network functions (NFs) that correspond to different service requests. Now, provisioning these NFs on the fog nodes also yields service delays due to the requirement for service migration from the cloud, i.e., offloading to the fog nodes. One solution to reduce this service delay is to provide cached copies of popular NFs in advance. Hence, it is critical to study function popularity and allow for content caching at the F-RAN. This is further a necessity given the limited resources at the fog nodes, thus requiring efficient resource management to enhance network capacity at reduced power and cost penalty. This paper proposes novel solutions that allocate popular NFs on the fog nodes to accelerate services for the terminals, namely, the clustered and distributed caching methods. The two methods are analyzed and compared against the baseline uncached provisioning schemes in terms of service delay, energy consumption, and cost.

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This paper is to present and discuss the new planned 380 kv transmission line performance under steady and transient states. Dynamic modeling and analysis of such inter-tie, wh ich is, proposed to transfer energy from west to south and vi ce versa will be demonstrated and discussed. The west-central-south Inter-tie links AlAula-Zaba-Tabuk-Tubajal-J awf-Hail. It is essential to investigate the transient overvoltage to assure steady and stable transmission over such inter-tie. Saudi Electricity Company (SEC) has been improving its grid to make the whole country as an interconnected system. Already East, Central and west were interconnected, yet mostly each is fed with its local generation. The SEC is planning to establish many inter-ties to strengthen the transient stability of its grid. The paper studies one of the important links of 380 KV between Tabouk and Tubarjal, which is a step towards connecting the West with the South region. Modeling and analysis using ET AP software will be utilized under different scenarios. Adoption of methods to stabilize and increase its power transmission is also discussed. Improvement of power system transients has been controlled by FACTS elements such the Static Var Compensators (SVC) in receipt of a broad significance since many technical studies have examined their effects on damping system oscillations and transient stability enhancement. Illustrations of the transient at each main generating or load bus will be checked in all inter-tie links. A brief review of possible means to solve the transient overvoltage problem using SVC element modeling will be discussed.