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This work is motivated by the need to develop decentralized peer‐to‐peer (P2P) approaches to support e‐learning and teaching activity in virtual universities. This paper aims to present the implementation of the JXTA‐based e‐learning P2P system.

The design and implementation of a smart box environment that will be used for stimulating the learners to increase the learning efficiency is shown. The smart box is integrated with the JXTA‐overlay by using efficient message sending between peers in the system.

The proposed e‐learning P2P system is a useful tool for monitoring and controlling learners' activity.

In the future, other effective stimulation for each learner using IC tag card will be added. Also, the Servo Motor has 12 control ports, so these will be used for implementing other stimulating functions. It is planned to extend the system with functionalities for presence mechanism of students in classrooms and activities.

The proposed system is evaluated by experimental results and it has a good performance.

This paper proposes and implements a novel e‐learning system, which is based on P2P, web and sensor technologies.

Satellite networking will be an important component of future ubiquitous communications systems. Satellite networks will be especially useful to interconnect remote sensor networks. Therefore, satellite networks should provide the needed QoS, differentiation of services and at the same time keep the required scalability. The purpose of this paper is to propose a new Diffserv‐based scheme of bandwidth allocation during congestion, called proportional allocation of bandwidth (PAB).

The paper suggests a method for implementing PAB without storing per‐flow state, which makes the scheme scalable and simple and shows, by simulation, the advantages of using PAB in IP satellite networks.

The paper finds that PAB can be used in geostationary earth orbit, MEO and low earth orbit satellite networks. In PAB, during congestion all flows get a share of IP available bandwidth, which is in proportion to their subscribed information rate.

The simulations described in this paper show that the performance of PAB scheme is good on congested satellite networks.

The growing use of internet-based learning (IBL) platforms in institutions of higher education is producing profound changes in the traditional teaching learning process worldwide. This paper aims to identify and understand the ways in which higher education institutions draw benefits by the use of such means, synthesizing the literature research.

The study synthesized the literature research by using a mixed method approach in which both Web of Science (WoS) and bibliographic techniques were used to retrieve the relevant data base.

The comprehensive review of the literature suggests that communication technology (CT), massive open online courseware (MOOCs), social networking sites (SNSs), blogs, real simple syndication (RSS) and YouTube are creating new possibilities and avenues of collaborative learning by transforming the traditional class and teacher-centric system.

Multiplicity of the IBL platforms and rapid technological obsolesce are some of the limitations of this paper.

The findings of this study are highly useful in developing a strategic framework to accelerate the integration of IBL platforms to make teaching learning process more interactive and informative.

Penetrator plays an important role in the exploration of Moon and Mars. The navigation method is a key technology during the development of penetrator. To meet the high accuracy requirements of Moon penetrator, this paper aims to propose two kinds of navigation systems.

The line of sight of vision sensor between the penetrator and Moon orbiter could be utilized as the measurement during the navigation system design. However, the analysis of observability shows that the navigation system cannot estimate the position and velocity of penetrator, when the line of sight measurement is the only resource of information. Therefore, the Doppler measurement due to the relative motion between penetrator and the orbiter is used as the supplement. The other option is the relative range measurement between penetrator and the orbiter. The sigma-point Kalman Filtering is implemented to fuse the information from the vision sensor and Doppler or rangefinder. The observability of two navigation system is analyzed.

The sigma-point Kalman filtering could be used based on vision sensor and Doppler radar or laser rangefinder to give an accurate estimation of Moon penetrator position and velocity without increasing the payload of Moon penetrator or decreasing the estimation accuracy. However, the simulation result shows that the last method is better. The observability analysis also proves this conclusion.

Two navigation systems are proposed, and the simulations show that both systems can provide accurate estimation of states of penetrator.

Two navigation methods are proposed, and the observability of these navigation systems is analyzed. The sigma-point Kalman filtering is first introduced to the vision-based navigation system for Moon penetrator to provide precision navigation during the descent phase of Moon penetrator.