Most load aware protocols for ad hoc networks use queue size as the main traffic load metric. However, this metric does not reflect the impact of channel contention from neighbor nodes. In this paper, we propose a load-aware routing protocol using two load metrics for route selection, which include MAC layer channel contention information, and the number of packets in the interface queue. MAC layer contention information provides an accurate estimation of neighbor nodes' state, and queue length provides a measurement of traffic load at the mobile node itself. This load-aware routing protocol can effectively balance the load and improve the performance of the ad hoc network. Impacts of these load metrics on the routing performance are studied, and simulations are conducted to evaluate our proposed scheme.

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BackgroundBlended learning that combines a modular object-oriented dynamic learning environment (Moodle) with face-to-face teaching was applied to a medical statistics course to improve learning outcomes and evaluate the impact factors of students’ knowledge, attitudes and practices (KAP) relating to e-learning.MethodsThe same real-name questionnaire was administered before and after the intervention. The summed scores of every part (knowledge, attitude and practice) were calculated using the entropy method. A mixed linear model was fitted using the SAS PROC MIXED procedure to analyse the impact factors of KAP.ResultsEducational reform, self-perceived character, registered permanent residence and hours spent online per day were significant impact factors of e-learning knowledge. Introversion and middle type respondents’ average scores were higher than those of extroversion type respondents. Regarding e-learning attitudes, educational reform, community number, Internet age and hours spent online per day had a significant impact. Specifically, participants whose Internet age was no greater than 6 years scored 7.00 points lower than those whose Internet age was greater than 10 years. Regarding e-learning behaviour, educational reform and parents’ literacy had a significant impact, as the average score increased 10.05 points (P < 0.0001).ConclusionsThis educational reform that combined Moodle with a traditional class achieved good results in terms of students’ e-learning KAP. Additionally, this type of blended course can be implemented in many other curriculums.

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Nanofiller/polymer nanocomposites are promising dielectrics for energy harvesting to be applied in wearable and flexible electronics. The structural design of the nanofillers plays a vital role to improve the energy storage performance of the related nanocomposites. Here, we fabricate a flexible device based on nonsolid titanium oxide (TiO x ) nanoparticles/poly(vinylidene fluoride) (PVDF) to achieve enhanced energy storage performance at low loading. The room-temperature oxidation method is used to oxidize two-dimensional MXene (Ti 3 C 2 T x ) flakes to form partially hollow TiO x nanoparticles. Taking advantage of this structure, the flexible TiO x nanoparticles/ PVDF nanocomposite with an ultralow loading content of 1 wt % nanofillers shows high energy storage performance, including a dielectric constant of ≈22 at 1 kHz, a breakdown strength of ≈480 MV m −1 , and an energy storage density of 7.43 J cm −3 . The finite element simulation further reveals that the optimization of the energy storage performance is ascribed to the lower electric potential among the partially hollow TiO x nanoparticles, which enhances the breakdown strength of the nanocomposites. This work opens a new avenue to structurally design and fabricate low-loading polymer-based nanocomposites for energy storage applications in next-generation flexible electronics.