Challenges of Blended Learning in Refugee Camps: When Internet Connectivity Fails, Human Connection Succeeds

In this paper, we studied the implementation of a course on global history as a blended section of a massive open online course (MOOC) and the learning challenges faced by the students in three crisis contexts: Azraq refugee camp (Jordan), Kakuma refugee camp (Kenya), and Amman urban refugee center (Jordan). The results showed that poor Internet connection in the camps severely impacted both students’ and instructors’ experience of the course. In the context of chronic Internet connectivity issues, the instructors had difficulties assessing their students’ needs and challenges. The results also showed that in light of these intermittent connection problems, the collaborative learning environment helped students navigate the challenges of a blended course. Also, the onsite visit by the online tutors and the face-to-face interactions that resulted from it had a noticeable impact on the human dynamics of the course by allowing instructors to provide targeted solutions to students’ problems as well as by building rapport between the students and the instructional team.

A scheme for stimulating message relaying cooperation

It is expected that all the nodes try their best to store and forward the messages in the intermittent connection network. However, due to the limited resources, such as memory, power, and transient communication chance, selfish nodes may relay the messages without responsibility. Stimulating selfish to behave normally could improve network performance. However, usually, it is difficult to distinguish the selfish behavior from the inability to relaying the message. By monitoring the behavior of relay nodes that messages are forwarding through, this article proposes a scheme that relays messages according to the reputation of intermediate nodes. The proposed reputation estimation scheme combines selfish behavior and inability behavior, and reveals very little private information for the protocol practice. There is a trade-off between the threshold and the performance. Too low value may not distinguish the selfish nodes. On the contrary, some normal nodes may excluded and cannot join the relaying and processing. Simulation effectively demonstrates that the reputation affects the node’s performance, and an appropriate reputation threshold value is useful for improving the network performance.

Lake or Estuary? Sedimentary and Benthic Foraminiferal Characterization of a Gulf of Mexico Coastal Dune Lake

Coastal dune lakes are shallow estuaries located within dune environments that share a permanent or intermittent connection with the sea. Because coastal dune lakes are found in few locations worldwide (e.g. Australia, New Zealand, Florida, etc.) they represent unique environments worthy of protection. However; there is a distinct lack of scientific data related to the function and ecology of coastal dune lakes, especially in the Gulf of Mexico. Therefore, the purpose of this study was to characterize the sedimentology and foraminifera of a representative coastal dune lake in Walton County, FL (i.e. Eastern Lake) and determine whether it shares geologic similarities with nearby estuaries. Ten Ekman sediment grab samples were collected along a transect spanning the length of Eastern Lake. The samples were processed to determine sedimentary properties and foraminiferal assemblages. Results from the sedimentary and foraminiferal analyses reveal 3 distinct depositional environments including: (1) a coarse grained, moderately well sorted, organic poor, sandy beach facies with both agglutinated and calcareous foraminifera, (2) a fine grained, very poorly sorted, organic rich central mud basin facies with mostly calcareous foraminifera, and (3) a coarse grained, poorly sorted, organic rich sandy marsh delta facies dominated by agglutinated foraminifera. These environments and foraminiferal patterns are also found in much larger nearby estuaries including Choctawhatchee Bay, Pensacola Bay, and Mobile Bay. Our results therefore suggest that coastal dune lakes may serve as down-scaled micro-estuaries and are functionally related to larger estuaries of the Gulf Coast despite their size.

Ant Colony Optimization Based Routing Scheme in Vehicular Delay Tolerant Networks

Delay Tolerant Networks finds its application in variety of environments and addresses issues like intermittent connection, long and variable delays and high latency. Vehicular Delay Tolerant Networks was introduced due to its various characteristic matches with DTNs. In particular class of VDTN there are two types of nodes: Stationary and Mobile nodes. Stationary nodes are deployed along the roadside and mobile nodes are constrained to move over the roads with variable speeds. This letter presents a new routing algorithm based on Ant Colony Optimization in Vehicular Delay Tolerant Network. We performed extensive simulation in ONE simulator and compare with Probabilistic Bundle Relaying Scheme to gauge the benefits of Ant Colony Optimization based scheme over Probabilistic Bundle Relaying scheme.