CSV: Content Service Offloading System with Vehicular Caching.

Vehicular caching (VC) has been considered as a promising technology to provide low end-to-end service latency and reduce the load of networks. However, it is difficult for VC to provide service continuity because of its opportunistic availability according to mobility. To mitigate this problem, we introduce a CSV: Content service offloading System with VC which can opportunistically distribute the load of the content server and support the service continuity. In CSV, the content service can be migrated between fog node (FN) and VC while maintaining the ongoing service without service disruption, which can opportunistically distribute the load of the content server and support the service continuity during migration. To assess the performance of CSV, we develop an analytical model for VC offloading efficiency. Extensive simulation results demonstrate that CSV can reduce the load of the content server compared to the conventional system.

Proactive Caching in D2D Assisted Multitier Cellular Network.

Cache-enabled networks suffer hugely from the challenge of content caching and content delivery. In this regard, cache-enabled device-to-device (D2D) assisted multitier cellular networks are expected to relieve the network data pressure and effectively solve the problem of content placement and content delivery. Consequently, the user can have a better opportunity to get their favored contents from nearby cache-enabled transmitters (CETs) through reliable and good-quality links; however, as expected, designing an effective caching policy is a challenging task due to the limited cache memory of CETs and uncertainty in user preferences. In this article, we introduce a joint content placement and content delivery technique for D2D assisted multitier cellular networks (D2DMCN). A support vector machine (SVM) is employed to predict the content popularity to determine which content is to be cached and where it is to be cached, thereby increasing the overall cache hit ratio (CHR). The content request is satisfied either by the neighboring node through the D2D link or by the cache-enabled base stations (BSs) of the multitier cellular networks (MCNs). Similarly, to solve the problem of optimal content delivery, the Hungarian algorithm is employed aiming to improve the quality of satisfaction. The simulation results indicate that the proposed content placement strategy effectively optimizes the overall cache hit ratio of the system. Similarly, an effective content delivery approach reduces the request content delivery delay and power consumption.

Next-Generation Payment System for Device-to-Device Content and Processing Sharing.

Recent developments in telecommunication world have allowed customers to share the storage and processing capabilities of their devices by providing services through fast and reliable connections. This evolution, however, requires building an incentive system to encourage information exchange in future telecommunication networks. In this study, we propose a mechanism to share bandwidth and processing resources among subscribers using smart contracts and a blockchain-based incentive mechanism, which is used to encourage subscribers to share their resources. We demonstrate the applicability of the proposed method through two use cases: (i) exchanging multimedia data and (ii) CPU sharing. We propose a universal user-to-user and user-to-operator payment system, named TelCash, which provides a solution for current roaming problems and establishes trust in X2X communications. TelCash has a great potential in solving the charges of roaming and reputation management (reliance) problems in telecommunications sector. We also show, by using a simulation study, that encouraging D2D communication leads to a significant increase in content quality, and there is a threshold after which downloading from base station is dramatically cut down and can be kept as low as 10%.

Lt: A Resource to Future-Proof the Laboratory in Uncertain Times.

The COVID-19 pandemic abruptly challenged educators to transition previously in-person courses to an online environment. This has been especially difficult for laboratory courses where students must experience the process of science to develop lab skills and scientific competencies. Due to the uncertainty caused by the pandemic, it is essential that instructional resources are flexible and robust for use in various potential learning environments. The Lt software platform (ADInstruments) is a resource designed to support in-person, online, and hybrid learning environments. Lt supports the in-person lab experience by integrating with data collection hardware and facilitating collaboration through group-based activity. In addition, the platform also provides several avenues for teaching online labs using the same experiments that would be done on campus. At home, students can analyze Lt's built-in example data, or be supplied with low-cost hardware to complete labs remotely. In conjunction with other online tools, Lt can support online group work and student collaboration. Lt hosts a wide range of pre-built lab experiments and activities covering neuroscience, anatomy, physiology, clinical health science, biology, and chemistry. Although the material can be used "out-of-the-box", the content is completely editable and new labs can be created. Feedback from students suggests that Lt has proved valuable for supporting flexible instructional practices during the pandemic.

Explicit Content Caching at Mobile Edge Networks with Cross-Layer Sensing.

The deployment density and computational power of small base stations (BSs) are expected to increase significantly in the next generation mobile communication networks. These BSs form the mobile edge network, which is a pervasive and distributed infrastructure that can empower a variety of edge/fog computing applications. This paper proposes a novel edge-computing application called explicit caching, which stores selective contents at BSs and exposes such contents to local users for interactive browsing and download. We formulate the explicit caching problem as a joint content recommendation, caching, and delivery problem, which aims to maximize the expected user quality-of-experience (QoE) with varying degrees of cross-layer sensing capability. Optimal and effective heuristic algorithms are presented to solve the problem. The theoretical performance bounds of the explicit caching system are derived in simplified scenarios. The impacts of cache storage space, BS backhaul capacity, cross-layer information, and user mobility on the system performance are simulated and discussed in realistic scenarios. Results suggest that, compared with conventional implicit caching schemes, explicit caching can better exploit the mobile edge network infrastructure for personalized content dissemination.

Joint Content Recommendation and Delivery in Mobile Wireless Networks with Outage Management.

Personalized content retrieval service has become a major information service that consumes a large portion of mobile Internet traffic. Joint content recommendation and delivery is a promising design philosophy that could effectively improve the overall user experience with personalized content retrieval services. Existing research mostly focused on a push-type design paradigm called proactive caching, which, however, has multiple inherent drawbacks such as high device cost and low energy efficiency. This paper proposes a novel, interactive joint content recommendation and delivery system as an alternative to overcome the drawbacks of proactive caching systems. We present several optimal and heuristic algorithms for the proposed system and analyze the system performance in terms of user interest and transmission outage probability. Some theoretical performance bounds of the system are also derived. The effectiveness of the proposed system and algorithms is validated by simulation results.

Enhancing the driving experience of smart city users based on content delivery framework for intelligent transportation systems.

Integration of several communication technologies that facilitate user access contributes to the rapid development of the smart city notion. Intelligent transportation systems (ITS) are introduced as part of smart city development to provide drivers with enhanced communication and information-sharing capabilities. The article introduces a novel ITS content delivery framework (CDF) that addresses communication outage issues. CDF-ITS uses End-to-end decision-making system modelling to examine factors such as communication, content distribution, and vehicle features. A suitable communication slot for vehicular users is determined by processing these characteristics based on outage time and variables. By allocating time-aware communication slots according to the classification of the propagation factor, outage problems may be reduced. End-to-end decision-making is used for classification and vehicle attribute balance, allowing immediate responses to user requests. The experimental outcomes show that the latency of 0.297 s, outage time of 0.0837, distributed messages of 276, and computing complexity of 11.87 are used to assess the proposed framework's efficiency across vehicle density and velocities.

Virus-Free Method to Control and Enhance Extracellular Vesicle Cargo Loading and Delivery.

Extracellular vesicles (EVs)─including exosomes and microvesicles─are involved in cell-cell communication. EVs encapsulate different types of molecules such as proteins or nucleotides and are long-lasting contenders for the establishment of personalized drug delivery systems. Recent studies suggest that the intrinsic capacities for uptake and cargo delivery of basic EVs might be too limited to serve as a potent delivery system. Here, we develop two synergistic methods to, respectively, control EV cargo loading and enhance EV cargo delivery through fusion without requirement for any viral fusogenic protein. Briefly, cargo loading is enabled through a reversible drug-inducible system that triggers the interaction between a cargo of interest and CD63, a well-established transmembrane EV marker. Enhanced cargo delivery is promoted by overexpressing Syncytin-1, an endogenous retrovirus envelop protein with fusogenic properties encoded by the human genome. We validate our bioengineered EVs in a qualitative and quantitative manner. Finally, we utilize this method to develop highly potent killer EVs, which contain a lethal toxin responsible for protein translation arrest and acceptor cell death. These advanced methods and future downstream applications may open promising doors in the manufacture of virus-free and EV-based delivery systems.

The Effect of Content Delivery Style on Student Performance in Anatomy.

The development of new technologies and ensuing pedagogical research has led many tertiary institutions to integrate and adopt online learning strategies. The authors of this study have incorporated online learning strategies into existing educational practices of a second year anatomy course, resulting in half of the course content delivered via face-to-face lectures, and half delivered online via tailored video vignettes, with accompanying worksheets and activities. The effect of the content delivery mode on student learning was analyzed by tailoring questions to content presented either face-to-face or online. Four practical tests were conducted across the semester with each consisting of four questions. Within each test, two questions were based on content delivered face-to-face, and two questions were based on content delivered online. Examination multiple choice questions were similarly divided and assessed. Findings indicate that student learning is consistent regardless of the mode of content delivery. However, student viewing habits had a significant impact on learning, with students who viewed videos multiple times achieving higher marks than those less engaged with the online content. Student comments also indicated that content delivery mode was not an influence on learning. Therefore student engagement, rather than the mode of content delivery, is a determinant of student learning and performance in human anatomy. Anat Sci Educ. © 2018 American Association of Anatomists.

Evolution and challenges of DNS-based CDNs.

DNS-based server redirecting is considered the most popular means of deploying CDNs. However, with the increasing use of remote DNS, DNS-based CDNs face a great challenge in performance degradation. To address this issue, encouraging progress has been made in both industry and research communities. In this article, state-of-art solutions for the remote DNS problem are discussed at first. Next, privacy concerns about DNS-based CDNs, including client location as well as redirection privacy, are identified and a representative solution is summarized. Finally, the solution is compared to those in prior works under different measures, and a discussion on DNS-based CDN applications is provided. A model is also established to deepen the understanding of CDN performance. We believe that this survey will shed light on the application of DNS-based CDNs, and it is expected to provide design guidelines to CDN service providers.

Students' Attitudes, Academic Performance and Preferences for Content Delivery in a Very Large Self-Care Course Redesign.

Objective. To evaluate students' performance/attitudes toward a flipped team-based learning (TBL) format in a "very large" self-care course based on student content delivery preference. Design. Third-year students enrolled in the course were surveyed regarding elements of redesign and homework completion. Additionally, their performance and incoming grade point average were evaluated. Assessment. A survey was completed by 286 of 305 students. Nineteen percent of respondents preferred traditional content delivery, whereas 30% preferred flipped TBL, 48% preferred a mixed format, and 3% had no preference. The grades achieved in the course were: A (49%), B (48%), C (3%) and D (0%). The majority completed "all" or "most" of the homework, appreciated attributes of course redesign, felt home preparation and in-class activities engaged them, and reported improved communication/evaluation skills. Content delivery preference significantly affected attitudes. Conclusion. Students positively received a flipped team-based learning classroom format, especially those who preferred flipped TBL or mixed content delivery. A minority with preference for traditional teaching style did not enjoy the new format; however, their academic performance did not differ significantly from those who did.