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Social media use carries both opportunities and risks for children and adolescents. In order to reduce the negative impacts of social media on youth, the authors focus our efforts on parental mediation of social media. Specifically, the purpose of this paper is to enhance the conceptualization and operationalization of parental mediation of social media.

First, the authors conducted focus groups with both children and parents in Singapore to categorize parental mediation strategies for social media and develop an initial scale of these strategies. Then, a survey was conducted with a nationally representative sample of 1,424 child participants and 1,206 parent participants in Singapore to develop and test the scale.

The focus group results identified four conceptually distinct parental mediation strategies for social media, labeled as active mediation, restrictive mediation, authoritarian surveillance, and non-intrusive inspection, and were used to develop an initial scale of these strategies. Based on the data from survey questionnaires, the authors investigated both inter-item and item-total correlations and performed confirmatory factor analysis (CFA), which developed and validated the scale of parental mediation of social media.

First, this research explained what parents do to manage children’s social media use and identified four conceptually distinct parental mediation strategies of social media, making a significant contribution to the parental mediation theory. Additionally, the research developed the first theory-derived, successively validated and reliable scale in parental mediation of social media.

Emerging real‐time multimedia services over IP have penetrated into the daily lives of normal people with the advent of advanced broadband communications and innovated interconnection technologies. To protect shared Internet from unfairness and further congestion collapse, rate control plays a crucial role for many multimedia services such as streaming applications. Streaming applications such as video on demand (VoD) or voice over IP (VoIP) services face some critical problems such as insufficient bandwidth and improper performance of transmission protocols. Besides, the new generation networks are anticipated to integrate all heterogeneous wired and wireless networks and offer seamless customized multimedia services anywhere, anytime. However, wireless networks usually with low and variable bandwidth, and non‐congestion related loss do bring the challenge to the existing transport protocol, such as TCP, TFRC etc.

The paper uses simulations and compares other methods. The purpose of this paper is to address these issues. The paper, proposes a rate control scheme named Jitter‐based Rate Control (JRC) to fit wired‐wireless hybrid network which has better performance than the current rate control scheme.

Extensive simulations and comparisons with other methods verify the effectiveness of our method for accurate and smooth estimation, no matter whether the wireless links are located.

The paper introduces the JRC.

The purpose of this paper is to propose an energy‐proportional routing (EPR) algorithm, which effectively extends the lifetimes of sensor networks.

The algorithm makes no specific assumption on network topology and hence is suitable for improving sensor networks with clustering. To optimally utilize energy, light‐load units – nodes or clusters that conserve energy are ideal candidates as intermediate units for forwarding data from others. To balance the load, first, the proposed algorithm predicts energy consumption of each node in each round. Then the algorithm controls the energy consumption of each unit as close as possible to the threshold representing the energy utilization mean value among clusters. Finally the algorithm checks satisfaction of the energy constraints in terms of distances and predicted data amounts. The proposed algorithm performs routing by determining whether a cluster head or a node should either undertake forwarding tasks or transmit data to intermediate hops. In this way, energy dissipation is evenly distributed to all units and the lifetime of the whole wireless sensor network is ultimately extended.

The algorithm applies hierarchically to different levels of network topology. In addition to experiments, the mathematical proofs of lifetime extension by the proposed routing algorithm are given in accordance with three widely accepted criteria – total energy dissipation, the number of live nodes in each round and the throughput (data amount per round).

A new routing algorithm is proposed.

Wireless local area networks (WLANs) are the predominant option for broadband wireless access network, and multiple access points (APs) will be much more available for wireless stations (WSTAs). Call admission control (CAC) on AP selection problem over 802.11 WLAN is a critical issue. In the existing architecture, strongest‐signal‐first is the default AP selection mechanism in 802.11 WLAN which uses the single criterion, received signal strength indicator, to select AP. However, this method suffers from bandwidth deficiency and unbalanced load among APs due to the uneven distribution of user load, thus degrading the system throughput. Instead, the purpose of this paper is to propose a multi‐criteria CAC on AP selection algorithms.

The distributed multi‐criteria considered in order are RSSI, minimum required bandwidth of WSTA, estimated effective bandwidth (EEB) and AP‐WSTA distance. A semiMarkov model considering both packet retransmission limit, packet error rate and collision effect is proposed to predict the system throughput and validated through simulation results. Two multi‐criteria AP selection algorithms after EEB is evaluated are proposed and compared based on this analytical model.

The proposed algorithms outperform the traditional SSF algorithm in terms of the balance index for AP and the average system throughput.

The paper presents performance analysis for multi‐criteria CAC for distributed access point selection in WLANs.

There are two types of medium access control (MAC) layer power‐saving (PS) protocols for IEEE 802.11‐based mobile ad hoc networks: synchronous and asynchronous ones. This paper seeks to propose a hybrid PS protocol to take advantages of both types of protocols.

The protocol utilizes the concept of dual‐channel and dual‐transmission‐range clustering. It divides all the hosts into clusters. Each cluster has a head and all the heads are organized as a virtual backbone to help route data. The protocol also utilizes the cluster head dismissal mechanism to avoid the ever‐increasing of cluster heads and to adapt to topology changing.

Simulation results demonstrate that the proposed protocol is more power‐efficient and more scalable than related protocols.

The proposed protocol is applicable to MANETs composed of hosts with single IEEE 802‐11 network interface card.