Communication Resources Allocation for Time Delay Reduction of Frequency Regulation Service in High Renewable Penetrated Power System

The high renewable penetrated power system has severe frequency regulation problems.Distributed resources can provide frequency regulation services but are limited by com-munication time delay.This paper proposes a communication resources allocation model to reduce communication time delay in frequency regulation service.Communication device resources and wireless spectrum resources are allocated to distributed resources when they participate in frequency regulation.We reveal impact of communication resources allocation on time delay reduction and frequency regulation performance.Besides,we study communication resources allocation solution in high renewable energy penetrated power systems.We provide a case study based on the HRP-38 system.Results show communication time delay decreases distributed resources'ability to provide frequency regulation service.On the other hand,allocating more communication resources to distributed resources'communica-tion services improves their frequency regulation performance.For power systems with renewable energy penetration above 70%,required communications resources are about five times as many as 30%renewable energy penetrated power systems to keep frequency performance the same.Index Terms-Communication resources allocation,commun-ication time delay,distributed resource,frequency regulation,high renewable energy penetrated power system.

The plant vascular systemⅠ:From resource allocation,inter-organ communication and defense,to evolution of the monocot cambium

In recent years, considerable attention has been paid to exploring the complex gene regulatory networks involved in the development of the plant vascular system. Such information is crucial to our understanding of the molecular and cellular events which give rise to the integrated tissues of the xylem and phloem, leading to the formation of structurally continuous conduits that interconnect various organs of the plant. Vascular development begins in the embryo to form progenitor cells, and upon germination, these progenitor cells and their decedents in the shoot and root meristems will form phloem and xylem, and the cambium.

The plant vascular system Ⅱ:From resource allocation,inter-organ communication and defense,to evolution of the monocot cambium

In this Special Issue, a focus is placed on the role of the xylem as an essential conduit for the long-distance delivery of water and mineral nutrients from the soil to the vegetative （above-ground） regions of the plant. Xylem cells destined to form tracheids or vessel members, which will make up the conduit for this water and mineral transport from the roots to the shoots, undergo apoptosis, a process of programmed cell death.

Multi-radio access based bandwidth allocation strategy for video communication in heterogeneous wireless networks

In order to make full use of the radio resource of heterogeneous wireless networks（HWNs） and promote the quality of service（Qo S） of multi-homing users for video communication, a bandwidth allocation algorithm based on multi-radio access is proposed in this paper. The proposed algorithm adopts an improved distributed common radio resource management（DCRRM） model which can reduce the signaling overhead sufficiently. This scheme can be divided into two phases. In the first phase, candidate network set of each user is obtained according to the received signal strength（RSS）. And the simple additive weighted（SAW） method is employed to determine the active network set. In the second phase, the utility optimization problem is formulated by linear combining of the video communication satisfaction model, cost model and energy efficiency model. And finding the optimal bandwidth allocation scheme with Lagrange multiplier method and Karush-Kuhn-Tucker（KKT） conditions. Simulation results show that the proposed algorithm promotes the network load performances and guarantees that users obtain the best joint utility under current situation.

Reviews and prospects in satellite range scheduling problem

With the increasing number of space satellites,the demand for satellite communication(including maneuvering,command uploading and data downloading)has also grown significantly.However,the actual communication resources of ground station are relatively limited,which leads to an oversubscribed problem.How to make use of limited ground station resources to complete satellite communication requests more fully and efficiently in the strict visible time is the focus of satellite range scheduling research.This paper reviews and looks forward to the research on Satellite Range Scheduling Problem(SRSP).Firstly,SRSP is defined as the scheduling problem of establishing communication between satellites and ground stations,and the classification and development of SRSP are introduced.Then,this paper analyzes three common problem description models,and establishes a mathematical model based on the analysis of optimization objectives and constraints.Thirdly,this paper classifies and summarizes the common solving methods of SRSP,and analyzes their characteristics and application scenarios.Finally,combined with the work in this paper,the future research direction of SRSP is envisioned.