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Future Internet, Volume 11, Issue 6 (June 2019) – 20 articles

Cover Story (view full-size image): Our paper examines the potential role of IoT technology in supporting a deeper understanding of the natural environment, reporting on the design and “in the wild” deployment of an environmental IoT in Wales. We describe the design of this system, its requirements and operational effectiveness for hydrological, soil and ethological scientists, and our experiences from building and maintaining the system and its deployment at a remote site in difficult conditions. The project utilised a field deployment of sensors augmented by services running on cloud, thus, offering a shared data repository to stakeholders. The paper concludes with the assertion that this combination of technologies can transform our understanding and management of the natural environment. While IoT deployments are often a solution searching for a problem, it is the other way round in environmental sciences. View this paper.
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2 pages, 156 KiB  
Editorial
Future Intelligent Systems and Networks
by Carmen De-Pablos-Heredero
Future Internet 2019, 11(6), 140; https://doi.org/10.3390/fi11060140 - 25 Jun 2019
Cited by 1 | Viewed by 2891
Abstract
The purpose of this Special Issue is to collect current developments and future directions of Future Intelligent Systems and Networks [...] Full article
(This article belongs to the Special Issue Future Intelligent Systems and Networks 2019)
18 pages, 1405 KiB  
Article
Location-Based Deferred Broadcast for Ad-Hoc Named Data Networking
by Meng Kuai and Xiaoyan Hong
Future Internet 2019, 11(6), 139; https://doi.org/10.3390/fi11060139 - 24 Jun 2019
Cited by 22 | Viewed by 4152
Abstract
The emerging connected and autonomous vehicles (CAVs) challenge ad hoc wireless multi-hop communications by mobility, large-scale, new data acquisition and computing patterns. The Named Data Networking (NDN) is suitable for such vehicle ad hoc networks due to its information centric networking approach. However, [...] Read more.
The emerging connected and autonomous vehicles (CAVs) challenge ad hoc wireless multi-hop communications by mobility, large-scale, new data acquisition and computing patterns. The Named Data Networking (NDN) is suitable for such vehicle ad hoc networks due to its information centric networking approach. However, flooding interest packets in ad-hoc NDN can lead to broadcast storm issue. Existing solutions will either increase the number of redundant interest packets or need a global knowledge about data producers. In this paper, a Location-Based Deferred Broadcast (LBDB) scheme is introduced to improve the efficiency and performance of interest broadcast in ad-hoc NDN. The scheme takes advantage of location information to set up timers when rebroadcasting an interest. The LBDB is implemented in V-NDN network architecture using ndnSIM simulator. Comparisons with several existing protocols are conducted in simulation. The results show that LBDB improves the overhead, the average number of hops and delay while maintaining an average satisfaction ratio when compared with several other broadcast schemes. The improvement can help offer timely data acquisition for quick responses in emergent CAV application situations. Full article
(This article belongs to the Special Issue Content Centric Future Internet Architectures)
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<p>Deferred Timer.</p>
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<p>Rebroadcast Forwarding Priority.</p>
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<p>Ad-Hoc Named Data Networking (NDN) Architecture.</p>
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<p>Interest and Data Forwarding Workflows.</p>
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<p>Open-Access Research Testbed (ORBIT) Experiment Topology.</p>
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<p>Interest Broadcast Evaluation Result.</p>
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<p>Simulation Scenario.</p>
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<p>Satisfaction Ratio.</p>
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<p>Average Hops.</p>
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<p>Normalized Transmission Overhead (interest and data).</p>
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<p>Average Delay.</p>
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<p>Impact of Max CA Timer.</p>
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<p>Impact of Max Forwarding Priority (FP) Timer.</p>
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16 pages, 1362 KiB  
Article
Data Anonymization for Hiding Personal Tendency in Set-Valued Database Publication
by Dedi Gunawan and Masahiro Mambo
Future Internet 2019, 11(6), 138; https://doi.org/10.3390/fi11060138 - 20 Jun 2019
Cited by 3 | Viewed by 3672
Abstract
Set-valued database publication has been increasing its importance recently due to its benefit for various applications such as marketing analysis and advertising. However, publishing a raw set-valued database may cause individual privacy breach such as the leakage of sensitive information like personal tendencies [...] Read more.
Set-valued database publication has been increasing its importance recently due to its benefit for various applications such as marketing analysis and advertising. However, publishing a raw set-valued database may cause individual privacy breach such as the leakage of sensitive information like personal tendencies when data recipients perform data analysis. Even though imposing data anonymization methods such as suppression-based methods and random data swapping methods to such a database can successfully hide personal tendency, it induces item loss from records and causes significant distortion in record structure that degrades database utility. To avoid the problems, we proposed a method based on swapping technique where an individual’s items in a record are swapped to items of the other record. Our swapping technique is distinct from existing one called random data swapping which yields much structure distortion. Even though the technique results in inaccuracy at a record level, it can preserve every single item in a database from loss. Thus, data recipients may obtain all the item information in an anonymized database. In addition, by carefully selecting a pair of records for item swapping, we can avoid excessive record structure distortion that leads to alter database content immensely. More importantly, such a strategy allows one to successfully hide personal tendency without sacrificing a lot of database utility. Full article
(This article belongs to the Special Issue Security and Privacy in Information and Communication Systems)
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<p>Website category.</p>
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<p>Swapping strategy.</p>
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<p>Comparison of the number of frequent itemset in anonymized datasets and original datasets.</p>
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<p>Comparison of the frequent itemset similarity among anonymized datasets to the original datasets.</p>
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<p><math display="inline"><semantics> <mrow> <mi>D</mi> <mi>i</mi> <mi>s</mi> <mi>s</mi> </mrow> </semantics></math> comparison among the anonymized datasets.</p>
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<p>Required computational time to generate <math display="inline"><semantics> <mover accent="true"> <mi mathvariant="script">D</mi> <mo>˜</mo> </mover> </semantics></math> among different methods.</p>
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20 pages, 1433 KiB  
Article
Negative Impact of Social Network Services Based on Stressor-Stress-Outcome: The Role of Experience of Privacy Violations
by Sanghyun Kim, Hyunsun Park and Moon Jong Choi
Future Internet 2019, 11(6), 137; https://doi.org/10.3390/fi11060137 - 20 Jun 2019
Cited by 19 | Viewed by 5554
Abstract
Social network service (SNS) information has benefited many individuals. However, as such information has increased exponentially, the number of SNS users has increased dramatically and negative effects of SNSs on users have emerged. Many SNS users experience negative psychological conditions such as fatigue, [...] Read more.
Social network service (SNS) information has benefited many individuals. However, as such information has increased exponentially, the number of SNS users has increased dramatically and negative effects of SNSs on users have emerged. Many SNS users experience negative psychological conditions such as fatigue, burnout, and stress. Thus, in this study, we investigated the SNS and user characteristics that affect SNS fatigue, living disorder, and reduced SNS use intention. We developed a research model to examine the impact of two SNS characteristics (irrelevant information overload and open reachability) and two user characteristics (engagement and maintaining self-reputation) on SNS fatigue. We also examined the role of the experience of privacy violations in the relationship between living disorder and reduced SNS use intention. We collected data from 579 SNS users and created a partial least squares structural equation model to test the hypotheses. The results of the analysis showed that three factors, other than open reachability, positively affected SNS fatigue. Furthermore, we found that SNS fatigue significantly affected living disorder and reduced SNS use intention, and that experience of privacy violations significantly affected the relationship between living disorder and reduced SNS use intention. These results expand our understanding of SNS fatigue and users’ negative behaviors. Full article
(This article belongs to the Section Techno-Social Smart Systems)
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<p>Stressor-stress-outcome (SSO) framework.</p>
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<p>Research model with hypotheses.</p>
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<p>The structural model for the direct effects (H1 to H6).</p>
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<p>(<b>a</b>) Main effect model; (<b>b</b>) interaction effect model.</p>
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22 pages, 2411 KiB  
Article
Developing Internet Online Procurement Frameworks for Construction Firms
by Rafikullah Deraman, Chen Wang, Jeffrey Boon Hui Yap, Heng Li and Faizul Azli Mohd-Rahim
Future Internet 2019, 11(6), 136; https://doi.org/10.3390/fi11060136 - 20 Jun 2019
Cited by 13 | Viewed by 4651
Abstract
Electronic purchasing or e-procurement saves millions of dollars yearly in transaction costs. E-procurement helps to cut down the supplier base, promotes paperless transactions, and increases transparency and accountability in the procurement process. Nonetheless, studies report that around 80% of e-procurement initiatives have met [...] Read more.
Electronic purchasing or e-procurement saves millions of dollars yearly in transaction costs. E-procurement helps to cut down the supplier base, promotes paperless transactions, and increases transparency and accountability in the procurement process. Nonetheless, studies report that around 80% of e-procurement initiatives have met with failure and failed to achieve the desired results. Although studies to better understand the Critical Success Factors (CSFs) of e-procurement implementation involving various industries have been on the rise, little is known about architecture engineering and construction (AEC) practices, which has led to limited development of pragmatic frameworks to uncover the factors. Thus, this study aims to identify those CSFs (predicting variables) which significantly contribute to e-procurement implementation success in the construction sector and to put forward for better implementation. Results from multiple regression analysis revealed five factors to be statistically significant predictors of success. Three factors were determined to be predictors of user satisfaction. Finally, internet online procurement frameworks were developed for the success of e-procurement implementation in the construction sector. Full article
(This article belongs to the Section Techno-Social Smart Systems)
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<p>Scatter plot of variables in correlation analysis.</p>
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<p>Scatter plot of correlation and linearity.</p>
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<p>Predicted path model of e-procurement implementation success.</p>
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<p>Histogram regression standardized residual.</p>
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<p>Normal (P-P) plot of regression standardized residual.</p>
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<p>e-procurement Implementation Success (ePIS) framework for project management success.</p>
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<p>e-procurement Implementation Success (ePIS) framework for user satisfaction.</p>
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17 pages, 931 KiB  
Article
The Interaction Effect of Type of Message X YouTuber’s Media Metrics on Customers’ Responses and the Moderation of Conformity Intention
by Melby Karina Zuniga Huertas and Tarcisio Duarte Coelho
Future Internet 2019, 11(6), 135; https://doi.org/10.3390/fi11060135 - 20 Jun 2019
Cited by 2 | Viewed by 3956
Abstract
This is a study of the way in which YouTubers’ media metrics influence the effect of their one-sided messages (1SMs) and two-sided messages (2SMs), providing theoretical explanations based on the elaboration likelihood model. Its main objective is the proposition and testing of: (i) [...] Read more.
This is a study of the way in which YouTubers’ media metrics influence the effect of their one-sided messages (1SMs) and two-sided messages (2SMs), providing theoretical explanations based on the elaboration likelihood model. Its main objective is the proposition and testing of: (i) the interaction effect between type of message and media metrics of the YouTuber on customers’ responses, and (ii) the moderation of individuals’ conformity intention for the interaction effect between type of message and media metrics on customers’ responses. The results of an experiment showed that high YouTubers’ media metrics have more effect for 1SMs and less effect for 2SMs. Additionally, conformity intention moderates the effect of the interaction type of message X media metrics. A high level of conformity intention neutralizes the interaction effect between YouTubers’ media metrics and message sidedness. This study makes a theoretical contribution to research into online content and information use, providing explanations of how media metrics of a vlog influence the effect of two types of messages. Full article
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<p>Proposed theoretical model for the interaction effect of type of message X YouTuber’s media metrics and the moderation of conformity intention.</p>
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<p>The effect of type of message on attitude towards the vlog moderated by the YouTuber’s numbers.</p>
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<p>The interaction effect between type of message and YouTuber’s media metrics on attitude towards the vlog for low conformity intention.</p>
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<p>The interaction effect between type of message and YouTuber’s media metrics on attitude towards the vlog for high conformity intention.</p>
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16 pages, 755 KiB  
Article
Bridging User Perception and Stickiness in Business Microblog Contexts: A Moderated Mediation Model
by Chien-Lung Hsu and Yi-Chuan Liao
Future Internet 2019, 11(6), 134; https://doi.org/10.3390/fi11060134 - 19 Jun 2019
Cited by 8 | Viewed by 4084
Abstract
This study develops a contingent mediation model to investigate whether user perception enhances customer stickiness through emotional connection and further assess such mediating effect varies with different adaptivity. A moderated mediation approach is adopted to test the hypotheses. Findings reveal the mediating role [...] Read more.
This study develops a contingent mediation model to investigate whether user perception enhances customer stickiness through emotional connection and further assess such mediating effect varies with different adaptivity. A moderated mediation approach is adopted to test the hypotheses. Findings reveal the mediating role of emotional connection on the link between perceived usefulness and customer stickiness, but not moderated by adaptivity. On the other hand, the results showed that the relationship between perceived ease of use and customer stickiness is not mediated by emotional connection; however, after considering the moderating effect, our results show that moderated mediation exists. Full article
(This article belongs to the Section Techno-Social Smart Systems)
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<p>Theoretical framework.</p>
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<p>The effect of moderated mediation (perceived usefulness -&gt; emotional connection -&gt; stickiness).</p>
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<p>The effect of moderated mediation (perceived ease of use -&gt; emotional connection -&gt; stickiness).</p>
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17 pages, 17442 KiB  
Article
Energy-Efficient Multi-User Routing in a Software-Defined Multi-Hop Wireless Network
by Ziqi Liu, Gaochao Xu, Peng Liu, Xiaodong Fu and Yang Liu
Future Internet 2019, 11(6), 133; https://doi.org/10.3390/fi11060133 - 17 Jun 2019
Cited by 5 | Viewed by 3517
Abstract
Software-defined networking (SDN) is an innovative architecture that designs a logical controller to manage and program the network based on the global view, providing more efficient management, better performance, and higher flexibility for the network. Therefore, applying the SDN concept in a multi-hop [...] Read more.
Software-defined networking (SDN) is an innovative architecture that designs a logical controller to manage and program the network based on the global view, providing more efficient management, better performance, and higher flexibility for the network. Therefore, applying the SDN concept in a multi-hop wireless network (MWN) has been proposed and extensively studied to overcome the challenges of MWN. In this paper, we propose an energy-efficient global routing algorithm for a software-defined multi-hop wireless network (SDMWN), which is able to get transmission paths for several users at the same time to minimize the global energy consumption with the premise of satisfying the QoS required by users. To this end, we firstly propose a Lagrange relaxation-based aggregated cost (LARAC) and K-Dijkstra combined algorithm to get the top K energy-minimum paths that satisfy the QoS in polynomial time. Then, we combine the alternative paths of each user obtained by K-LARAC and propose an improved genetic algorithm to solve the global routing strategy. The simulation results show that the proposed K-LARAC and genetic algorithm combined method has the ability to obtain an approximate optimal solution with lower time cost. Full article
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<p>System architecture.</p>
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<p>The network of the simulation.</p>
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<p>User number vs. execution time. LARAC, Lagrange relaxation-based aggregated cost. DBFS, Delay-constrained Bellman–Ford.</p>
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<p>User number vs. accuracy.</p>
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<p>User number vs. energy consumption.</p>
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20 pages, 2491 KiB  
Article
A Choreography-Based and Collaborative Road Mobility System for L’Aquila City
by Marco Autili, Amleto Di Salle, Francesco Gallo, Claudio Pompilio and Massimo Tivoli
Future Internet 2019, 11(6), 132; https://doi.org/10.3390/fi11060132 - 14 Jun 2019
Cited by 9 | Viewed by 4457
Abstract
Next Generation Internet (NGI) is the European initiative launched to identify the future internet technologies, designed to serve the needs of the digitalized society while ensuring privacy, trust, decentralization, openness, inclusion, and business cooperation. NGI provides efficient support to promote diversity, decentralization and [...] Read more.
Next Generation Internet (NGI) is the European initiative launched to identify the future internet technologies, designed to serve the needs of the digitalized society while ensuring privacy, trust, decentralization, openness, inclusion, and business cooperation. NGI provides efficient support to promote diversity, decentralization and the growth of disruptive innovation envisioned by smart cities. After the earthquake of 6 April 2009, the city of L’Aquila is facing a massive and innovative reconstruction process. As a consequence, nowadays, the L’Aquila city can be considered as a living laboratory model for applications within the context of smart cities. This paper describes and evaluates the realization of a Collaborative Road Mobility System (CRMS) for L’Aquila city by using our CHOReVOLUTION approach for the automated choreography production. The CRMS allows vehicles and transport infrastructure to interconnect, share information and use it to coordinate their actions. Full article
(This article belongs to the Special Issue 10th Anniversary Feature Papers)
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<p>BPMN2 choreography diagram example.</p>
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<p>Choreography architectural style (a sample instance of).</p>
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<p>CHOReVOLUTION synthesis process.</p>
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<p>CHOReVOLUTION IDRE overview.</p>
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<p>Eco Driving Planning choreography.</p>
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<p>Smart Data Collection choreography.</p>
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<p>ECO Driving Planning architecture.</p>
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<p>Smart Data Collector architecture.</p>
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13 pages, 2556 KiB  
Article
Time Series Irradiance Synthesizer for Optical GEO Satellite Downlinks in 5G Networks
by Theodore T. Kapsis, Nikolaos K. Lyras, Charilaos I. Kourogiorgas and Athanasios D. Panagopoulos
Future Internet 2019, 11(6), 131; https://doi.org/10.3390/fi11060131 - 13 Jun 2019
Cited by 6 | Viewed by 3878
Abstract
Next generation 5G networks generate a need for broadband, low latency and power efficient backhauling and data-relay services. In this paper, optical satellite communications links, as an integrated component of 5G networks, are studied. More specifically, the Geostationary (GEO) satellite-to-ground optical communication link [...] Read more.
Next generation 5G networks generate a need for broadband, low latency and power efficient backhauling and data-relay services. In this paper, optical satellite communications links, as an integrated component of 5G networks, are studied. More specifically, the Geostationary (GEO) satellite-to-ground optical communication link is investigated. Long-term irradiance statistics based on experimental measurements from the ARTEMIS program are presented and a new time series generator related to the received irradiance/power fluctuations due to atmospheric turbulence is reported. The proposed synthesizer takes into consideration the turbulence-induced scintillation effects that deteriorate the laser beam propagation, on the assumption of the Kolmogorov spectrum. The modeling is based on Rytov theory regarding weak turbulence conditions with the incorporation of first order stochastic differential equations. Summing up, the time series synthesizer is validated in terms of first and second order statistics with experimental results from the European Space Agency‘s ARTEMIS experimental optical downlink and simulated received power statistics for various weather conditions are presented using the proposed validated methodology. Some important conclusions are drawn. Full article
(This article belongs to the Special Issue Satellite Communications in 5G Networks)
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<p>Setup of the ARTEMIS optical experiments.</p>
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<p>Received irradiance time series as measured by optical ground station (OGS) and LUCE terminals.</p>
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<p>The power spectral density (PSD) of scintillation decreases with −80/3 dB/decade.</p>
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<p>First order irradiance statistics validation for session on 13/09/2003 23:30. (<b>a</b>) Normalized probability density function (PDF) of measured data vs. Normalized PDF of generated data; (<b>b</b>) cumulative distribution function (CDF) of measured data vs. CDF of generated data.</p>
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<p>Second order irradiance statistics validation for session on 13/09/2003 23:30. PSD of measured data vs. PSD of generated data.</p>
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<p>First order irradiance statistics validation for session on 16/09/2003 21:10. (<b>a</b>) Normalized PDF of measured data vs. Normalized PDF of generated data; (<b>b</b>) CDF of measured data vs. CDF of generated data.</p>
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<p>Second order irradiance statistics validation for session on 16/09/2003 21:10. PSD of measured data vs. PSD of generated data.</p>
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<p>First order irradiance statistics validation for session on 10/09/2003 20:10. (<b>a</b>) Normalized PDF of measured data vs. Normalized PDF of generated data; (<b>b</b>) CDF of measured data vs. CDF of generated data.</p>
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<p>Second order irradiance statistics validation for session on 10/09/2003 20:10. PSD of measured data vs. PSD of generated data.</p>
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<p>Downlink received power for various weather conditions.</p>
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16 pages, 1863 KiB  
Article
Digital Marketing Actions That Achieve a Better Attraction and Loyalty of Users: An Analytical Study
by Juan José López García, David Lizcano, Celia MQ Ramos and Nelson Matos
Future Internet 2019, 11(6), 130; https://doi.org/10.3390/fi11060130 - 8 Jun 2019
Cited by 61 | Viewed by 29398
Abstract
Currently, the digital economy contributes decisively to an increase in competitiveness, especially as a digital transformation involves migrating to new technological models where digital marketing is a key part of growth and user loyalty strategies. Internet and Digital Marketing have become important factors [...] Read more.
Currently, the digital economy contributes decisively to an increase in competitiveness, especially as a digital transformation involves migrating to new technological models where digital marketing is a key part of growth and user loyalty strategies. Internet and Digital Marketing have become important factors in campaigns, which attract and retain Internet users. This study aims to identify the main ways in which users can be gained and retained by using Digital Marketing. The Delphi method with in-depth interviews was the methodology used in this study. The results of the research show the most important actions for achieving user recruitment and loyalty with Digital Marketing from the opinions of consulted experts. The limitations of this study are those related to the number of experts included in the study, and the number of research papers consulted in the literature review. The literature review and the results of this research are used to propose new solid research with a consolidated critical methodology. This research deals with a new approach that will optimize web technologies for the evolution of user trends, and therefore, will be of academic and professional use for marketing managers and web solution developers. The conclusions of the investigation show the key factors, discarding others that do not affect the optimization of conversions in B2C businesses such as the duration of the session and the rebound percentage. Likewise, the results of the research identify the specific actions that must be carried out to attract and retain users in B2C companies that use the Digital Marketing ecosystem on the Internet. The requirements for companies that wish to implement a model to optimize conversions using the current digital economy are also shown. Full article
(This article belongs to the Section Techno-Social Smart Systems)
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<p>Diagram showing the stages in a Delphi study. (Based on Hsu and Sandford, 2007; Torrecilla-Salinas et al., 2019 [<a href="#B46-futureinternet-11-00130" class="html-bibr">46</a>,<a href="#B47-futureinternet-11-00130" class="html-bibr">47</a>].</p>
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<p>Control and Monitoring of recruitment actions.</p>
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<p>Search Engine Marketing actions used to capture leads on the Internet.</p>
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<p>Recruitment using social networks.</p>
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<p>Comparison of leads recruitment on social networks.</p>
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27 pages, 35040 KiB  
Article
The Design and Deployment of an End-To-End IoT Infrastructure for the Natural Environment
by Vatsala Nundloll, Barry Porter, Gordon S. Blair, Bridget Emmett, Jack Cosby, Davey L. Jones, Dave Chadwick, Ben Winterbourn, Philip Beattie, Graham Dean, Rory Shaw, Wayne Shelley, Mike Brown and Izhar Ullah
Future Internet 2019, 11(6), 129; https://doi.org/10.3390/fi11060129 - 7 Jun 2019
Cited by 17 | Viewed by 6378
Abstract
Internet of Things (IoT) systems have seen recent growth in popularity for city and home environments. We report on the design, deployment, and use of the IoT infrastructure for environmental monitoring and management. Working closely with hydrologists, soil scientists, and animal behaviour scientists, [...] Read more.
Internet of Things (IoT) systems have seen recent growth in popularity for city and home environments. We report on the design, deployment, and use of the IoT infrastructure for environmental monitoring and management. Working closely with hydrologists, soil scientists, and animal behaviour scientists, we successfully deployed and utilised a system to deliver integrated information across these two fields in the first such example of real-time multidimensional environmental science. We describe the design of this system; its requirements and operational effectiveness for hydrological, soil, and ethological scientists; and our experiences from building, maintaining, and using the deployment at a remote site in difficult conditions. Based on this experience, we discuss key future work for the IoT community when working in these kinds of environmental deployments. Full article
(This article belongs to the Special Issue Cloud Computing and Internet of Things)
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<p>A wide-area view of the geographical region of our deployment. The areas marked in dotted lines are those actively studied by the environmental science team using various types of traditional (non-IoT (Internet of Things)) measurement equipment. The primary site used for our IoT project is that marked as “Hiraethlyn Improved”.</p>
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<p>The architecture of our IoT system: Further Internet services connect to the cloud server, providing scientific modelling or lightweight applications to visualise data.</p>
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<p>The deployment location of our IoT system, showing a geographical view of the entire deployment as well as a detailed technical view of the field of study in hydrological terms: Mobile (livestock) nodes are not shown on the geographical view, but tracked animals are located within the treeline enclosing the area marked “field of study” (courtesy of Satellite image from Google Earth).</p>
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<p>IoT nodes (from left to right: relay, soil node, and livestock node on a sheep).</p>
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<p>Standard soil node.</p>
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<p>Super soil node.</p>
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<p>Sensor inputs on our soil nodes, mixing a large quantity of cheap Grove sensors with a small number of high-quality Acclima sensors.</p>
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<p>The relay node.</p>
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<p>Node registration.</p>
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<p>Environmental IoT dashboard application.</p>
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<p>Readings for one soil node.</p>
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<p>Number of nodes in the field.</p>
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<p>Hierathlyn field deployment site.</p>
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<p>Images from our deployment site. Clockwise from top left: initial site reconnaissance with environmental scientists; the site as we initially found it; a protective dome over a soil sensing node; configuring the relay node; constructing hardware at the site; and the location of the Internet gateway node.</p>
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<p>A corroded soil sensor.</p>
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<p>Soil data.</p>
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<p>Sheep data.</p>
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<p>Map showing semantically enriched IoT data.</p>
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<p>The complementarity of IoT, cloud, and data science is a key field of future work for integrative research efforts each needing to understand the role and capabilities of the others.</p>
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22 pages, 8056 KiB  
Article
Distributed Edge Computing to Assist Ultra-Low-Latency VANET Applications
by Andrei Vladyko, Abdukodir Khakimov, Ammar Muthanna, Abdelhamied A. Ateya and Andrey Koucheryavy
Future Internet 2019, 11(6), 128; https://doi.org/10.3390/fi11060128 - 4 Jun 2019
Cited by 37 | Viewed by 6003
Abstract
Vehicular ad hoc networks (VANETs) are a recent class of peer-to-peer wireless networks that are used to organize the communication and interaction between cars (V2V), between cars and infrastructure (V2I), and between cars and other types of nodes (V2X). These networks are based [...] Read more.
Vehicular ad hoc networks (VANETs) are a recent class of peer-to-peer wireless networks that are used to organize the communication and interaction between cars (V2V), between cars and infrastructure (V2I), and between cars and other types of nodes (V2X). These networks are based on the dedicated short-range communication (DSRC) IEEE 802.11 standards and are mainly intended to organize the exchange of various types of messages, mainly emergency ones, to prevent road accidents, alert when a road accident occurs, or control the priority of the roadway. Initially, it was assumed that cars would only interact with each other, but later, with the advent of the concept of the Internet of things (IoT), interactions with surrounding devices became a demand. However, there are many challenges associated with the interaction of vehicles and the interaction with the road infrastructure. Among the main challenge is the high density and the dramatic increase of the vehicles’ traffic. To this end, this work provides a novel system based on mobile edge computing (MEC) to solve the problem of high traffic density and provides and offloading path to vehicle’s traffic. The proposed system also reduces the total latency of data communicated between vehicles and stationary roadside units (RSUs). Moreover, a latency-aware offloading algorithm is developed for managing and controlling data offloading from vehicles to edge servers. The system was simulated over a reliable environment for performance evaluation, and a real experiment was conducted to validate the proposed system and the developed offloading method. Full article
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<p>(<b>a</b>) General structure of the traditional vehicular ad-hoc network (VANET). (<b>b</b>) The end-to-end system structure of the proposed novel VANET system.</p>
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<p>Layer system of the proposed multilevel VANET system.</p>
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<p>Bandwidth performance of the considered VANET system.</p>
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<p>Packet delivery time with the distance between roadside unit RSU stations for scenario (A).</p>
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<p>The rate of data offloaded to the backhaul network for scenario (A).</p>
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<p>Packet delivery time with the distance between RSU stations for scenario (B).</p>
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<p>The rate of data offloaded to the backhaul network for scenario (B).</p>
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<p>Packet delivery time for with the distance between RSU stations for scenario (C).</p>
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<p>The rate of data offloaded to the backhaul network for scenario (C).</p>
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<p>The average latency of handling the first group of tasks.</p>
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<p>The average latency of handling the second group of tasks.</p>
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<p>The average latency of handling the third group of tasks.</p>
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<p>The average latency of handling the fourth group of tasks.</p>
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<p>The average latency of handling the fifth group of tasks.</p>
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<p>System comparison in terms of task blocking.</p>
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<p>Developed model.</p>
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<p>Used devices.</p>
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30 pages, 790 KiB  
Article
Cyber-Storms Come from Clouds: Security of Cloud Computing in the IoT Era
by Michele De Donno, Alberto Giaretta, Nicola Dragoni, Antonio Bucchiarone and Manuel Mazzara
Future Internet 2019, 11(6), 127; https://doi.org/10.3390/fi11060127 - 4 Jun 2019
Cited by 43 | Viewed by 9089
Abstract
The Internet of Things (IoT) is rapidly changing our society to a world where every “thing” is connected to the Internet, making computing pervasive like never before. This tsunami of connectivity and data collection relies more and more on the Cloud, where data [...] Read more.
The Internet of Things (IoT) is rapidly changing our society to a world where every “thing” is connected to the Internet, making computing pervasive like never before. This tsunami of connectivity and data collection relies more and more on the Cloud, where data analytics and intelligence actually reside. Cloud computing has indeed revolutionized the way computational resources and services can be used and accessed, implementing the concept of utility computing whose advantages are undeniable for every business. However, despite the benefits in terms of flexibility, economic savings, and support of new services, its widespread adoption is hindered by the security issues arising with its usage. From a security perspective, the technological revolution introduced by IoT and Cloud computing can represent a disaster, as each object might become inherently remotely hackable and, as a consequence, controllable by malicious actors. While the literature mostly focuses on the security of IoT and Cloud computing as separate entities, in this article we provide an up-to-date and well-structured survey of the security issues of cloud computing in the IoT era. We give a clear picture of where security issues occur and what their potential impact is. As a result, we claim that it is not enough to secure IoT devices, as cyber-storms come from Clouds. Full article
(This article belongs to the Special Issue Cloud Computing and Internet of Things)
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<p>A broader definition of IoT (adapted from [<a href="#B21-futureinternet-11-00127" class="html-bibr">21</a>]): a two layered architecture in which End/IoT devices strongly rely on the Cloud.</p>
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<p>NIST Cloud computing reference architecture (source [<a href="#B36-futureinternet-11-00127" class="html-bibr">36</a>]).</p>
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<p>Scope of control between provider and consumer (source [<a href="#B36-futureinternet-11-00127" class="html-bibr">36</a>]).</p>
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<p>Simplified Cloud reference architecture.</p>
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<p>Classification of Cloud security issues.</p>
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25 pages, 3444 KiB  
Article
CKMI: Comprehensive Key Management Infrastructure Design for Industrial Automation and Control Systems
by Pramod T. C., Thejas G. S., S. S. Iyengar and N. R. Sunitha
Future Internet 2019, 11(6), 126; https://doi.org/10.3390/fi11060126 - 4 Jun 2019
Cited by 9 | Viewed by 5511
Abstract
Industrial Automation and Control Systems (IACS) are broadly utilized in critical infrastructures for monitoring and controlling the industrial processes remotely. The real-time transmissions in such systems provoke security breaches. Many security breaches have been reported impacting society severely. Hence, it is essential to [...] Read more.
Industrial Automation and Control Systems (IACS) are broadly utilized in critical infrastructures for monitoring and controlling the industrial processes remotely. The real-time transmissions in such systems provoke security breaches. Many security breaches have been reported impacting society severely. Hence, it is essential to achieve secure communication between the devices for creating a secure environment. For this to be effective, the keys used for secure communication must be protected against unauthorized disclosure, misuse, alteration or loss, which can be taken care of by a Key Management Infrastructure. In this paper, by considering the generic industrial automation network, a comprehensive key management infrastructure (CKMI) is designed for IACS. To design such an infrastructure, the proposed scheme employs ECDH, matrix method, and polynomial crypto mechanisms. The proposed design handles all the standard key management operations, viz. key generation, device registration, key establishment, key storage, device addition, key revocation, key update, key recovery, key archival, and key de-registration and destruction. The design supports secure communication between the same and different levels of IACS devices. The proposed design can be applied for major industrial automation networks to handle the key management operations. The performance analysis and implementation results highlight the benefits of the proposed design. Full article
(This article belongs to the Special Issue Next-Generation Public-Key Infrastructures)
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<p>Industrial automation and control systems.</p>
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<p>Key management states.</p>
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<p>Matrix method operation.</p>
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<p>Key storage.</p>
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<p>Device addition operation.</p>
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<p>Secure Communication between field and control level devices.</p>
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<p>Proposed CKMI design for IACS.</p>
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<p>Test setup of industrial automation network with key establishment schemes.</p>
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22 pages, 604 KiB  
Article
Joint Location-Dependent Pricing and Request Mapping in ICN-Based Telco CDNs For 5G
by Mingshuang Jin, Hongbin Luo, Shuai Gao and Bohao Feng
Future Internet 2019, 11(6), 125; https://doi.org/10.3390/fi11060125 - 3 Jun 2019
Cited by 2 | Viewed by 3708
Abstract
Telco content delivery networks (CDNs) have envisioned building highly distributed and cloudified sites to provide a high-quality CDN service in the 5G era. However, there are still two open problems to be addressed. First, telco CDNs are operated upon the underlay network evolving [...] Read more.
Telco content delivery networks (CDNs) have envisioned building highly distributed and cloudified sites to provide a high-quality CDN service in the 5G era. However, there are still two open problems to be addressed. First, telco CDNs are operated upon the underlay network evolving towards information-centric networking (ICN). Different from CDNs that perform on the application layer, ICN enables information-centric forwarding to the network layer. Thus, it is challenging to take advantage of the benefits of both ICN and CDN to provide a high-quality content delivery service in the context of ICN-based telco CDNs. Second, bandwidth pricing and request mapping issues in ICN-based telco CDNs have not been thoroughly studied. In this paper, we first propose an ICN-based telco CDN framework that integrates the information-centric forwarding enabled by ICN and the powerful edge caching enabled by telco CDNs. Then, we propose a location-dependent pricing (LDP) strategy, taking into consideration the congestion level of different sites. Furthermore, on the basis of LDP, we formulate a price-aware request mapping (PARM) problem, which can be solved by existing linear programming solvers. Finally, we conduct extensive simulations to evaluate the effectiveness of our design. Full article
(This article belongs to the Special Issue Information-Centric Networking (ICN))
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<p>Telco content delivery network (CDN) service scenario in comparison with traditional CDN scenario.</p>
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<p>The relationship between the modules in our design.</p>
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<p>The relationship between congestion level and bandwidth price.</p>
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<p>LDP Prices in Traffic Pattern 1.</p>
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<p>LDP prices in Traffic Pattern 2.</p>
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<p>LDP prices in Traffic Pattern 3.</p>
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<p>LDP prices in Traffic Pattern 4.</p>
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<p>Comparison of variation of CDN sites.</p>
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<p>Comparison of total Bandwidth Cost.</p>
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<p>Comparison of total bandwidth payment.</p>
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<p>Comparison of application’s average latency.</p>
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<p>Impact of <math display="inline"><semantics> <mi>τ</mi> </semantics></math> on sites’ variation in PARM.</p>
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<p>Impact of <math display="inline"><semantics> <mi>τ</mi> </semantics></math> on total bandwidth cost in PARM.</p>
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<p>Impact of <math display="inline"><semantics> <mi>τ</mi> </semantics></math> on total payment in PARM.</p>
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<p>Impact of <math display="inline"><semantics> <mi>τ</mi> </semantics></math> on average latency in PARM.</p>
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<p>Impact of <math display="inline"><semantics> <msub> <mi>P</mi> <mrow> <mi>m</mi> <mi>a</mi> <mi>x</mi> </mrow> </msub> </semantics></math> on sites’ variation in PARM.</p>
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<p>Impact of <math display="inline"><semantics> <msub> <mi>P</mi> <mrow> <mi>m</mi> <mi>a</mi> <mi>x</mi> </mrow> </msub> </semantics></math> on total bandwidth cost in PARM.</p>
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<p>Impact of <math display="inline"><semantics> <msub> <mi>P</mi> <mrow> <mi>m</mi> <mi>a</mi> <mi>x</mi> </mrow> </msub> </semantics></math> on total payment in PARM.</p>
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<p>Impact of <math display="inline"><semantics> <msub> <mi>P</mi> <mrow> <mi>m</mi> <mi>a</mi> <mi>x</mi> </mrow> </msub> </semantics></math> on average latency in PARM.</p>
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15 pages, 1625 KiB  
Article
Indoor Vehicles Geolocalization Using LoRaWAN
by Pietro Manzoni, Carlos T. Calafate, Juan-Carlos Cano and Enrique Hernández-Orallo
Future Internet 2019, 11(6), 124; https://doi.org/10.3390/fi11060124 - 31 May 2019
Cited by 28 | Viewed by 5877
Abstract
One of the main drawbacks of Global Navigation Satellite Sytems (GNSS) is that they do not work indoors. When inside, there is often no direct line from the satellite signals to the device and the ultra high frequency (UHF) used is blocked by [...] Read more.
One of the main drawbacks of Global Navigation Satellite Sytems (GNSS) is that they do not work indoors. When inside, there is often no direct line from the satellite signals to the device and the ultra high frequency (UHF) used is blocked by thick, solid materials such as brick, metal, stone or wood. In this paper, we describe a solution based on the Long Range Wide Area Network (LoRaWAN) technology to geolocalise vehicles indoors. Through estimation of the behaviour of a LoRaWAN channel and using trilateration, the localisation of a vehicle can be obtained within a 20–30 m range. Indoor geolocation for Intelligent Transporation Systems (ITS) can be used to locate vehicles of any type in underground parkings, keep a platoon of trucks in formation or create geo-fences, that is, sending an alert if an object moves outside a defined area, like a bicycle being stolen. Routing of heavy vehicles within an industrial setting is another possibility. Full article
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<p>The architecture of a generic Long Range Wide Area Network (LoRaWAN) system.</p>
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<p>The architecture of the proposed system.</p>
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<p>The metadata content provided by the networks server.</p>
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<p>Graphical representation of the trilateration algorithm.</p>
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<p>Location for the localisation experiments, the underground car parks of the UPV. (<b>a</b>) north-south orientation; (<b>b</b>) east-west orientation.</p>
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<p>The map of the localisation experiments with the position of the gateways and of the client.</p>
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<p>The hardware used for the experiments. On top the two clients used (<b>a</b>) a Whisper Node by Wisen, (<b>b</b>) an Adafruit Feather 32u4, on bottom (<b>c</b>,<b>d</b>) two gateways based on a LoPy by Pycom.</p>
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<p>Variation and stability of the Received Signal Strength Indicator (RSSI) with two different spreading factors and three distances.</p>
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<p>Cumulative distribution of the RSSI with two different spreading factors at 50 m.</p>
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<p>Q-Q plot of the RSSI with two different spreading factors at 50 m.</p>
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<p>The variation of the precision of the localisation in the scenario considered.</p>
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16 pages, 7862 KiB  
Article
Vehicle Speed Estimation Based on 3D ConvNets and Non-Local Blocks
by Huanan Dong, Ming Wen and Zhouwang Yang
Future Internet 2019, 11(6), 123; https://doi.org/10.3390/fi11060123 - 30 May 2019
Cited by 22 | Viewed by 4979
Abstract
Vehicle speed estimation is an important problem in traffic surveillance. Many existing approaches to this problem are based on camera calibration. Two shortcomings exist for camera calibration-based methods. First, camera calibration methods are sensitive to the environment, which means the accuracy of the [...] Read more.
Vehicle speed estimation is an important problem in traffic surveillance. Many existing approaches to this problem are based on camera calibration. Two shortcomings exist for camera calibration-based methods. First, camera calibration methods are sensitive to the environment, which means the accuracy of the results are compromised in some situations where the environmental condition is not satisfied. Furthermore, camera calibration-based methods rely on vehicle trajectories acquired by a two-stage tracking and detection process. In an effort to overcome these shortcomings, we propose an alternate end-to-end method based on 3-dimensional convolutional networks (3D ConvNets). The proposed method bases average vehicle speed estimation on information from video footage. Our methods are characterized by the following three features. First, we use non-local blocks in our model to better capture spatial–temporal long-range dependency. Second, we use optical flow as an input in the model. Optical flow includes the information on the speed and direction of pixel motion in an image. Third, we construct a multi-scale convolutional network. This network extracts information on various characteristics of vehicles in motion. The proposed method showcases promising experimental results on commonly used dataset with mean absolute error (MAE) as 2.71 km/h and mean square error (MSE) as 14.62 . Full article
(This article belongs to the Section Big Data and Augmented Intelligence)
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<p>Flow Chart of Our Method.</p>
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<p>3D Conv VS (2+1)D Conv.</p>
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<p>Non-local block.</p>
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<p>Multi-scale CNN.</p>
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<p>Model Architecture.</p>
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<p>Data sample.</p>
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20 pages, 449 KiB  
Article
Survey and Perspectives of Vehicular Wi-Fi versus Sidelink Cellular-V2X in the 5G Era
by Alessandro Bazzi, Giammarco Cecchini, Michele Menarini, Barbara M. Masini and Alberto Zanella
Future Internet 2019, 11(6), 122; https://doi.org/10.3390/fi11060122 - 29 May 2019
Cited by 114 | Viewed by 10370
Abstract
The revolution of cooperative connected and automated vehicles is about to begin and a key milestone is the introduction of short range wireless communications between cars. Given the tremendous expected market growth, two different technologies have been standardized by international companies and consortia, [...] Read more.
The revolution of cooperative connected and automated vehicles is about to begin and a key milestone is the introduction of short range wireless communications between cars. Given the tremendous expected market growth, two different technologies have been standardized by international companies and consortia, namely IEEE 802.11p, out for nearly a decade, and short range cellular-vehicle-to-anything (C-V2X), of recent definition. In both cases, evolutions are under discussion. The former is only decentralized and based on a sensing before transmitting access, while the latter is based on orthogonal resources that can be also managed by an infrastructure. Although studies have been conducted to highlight advantages and drawbacks of both, doubts still remain. In this work, with a reference to the literature and the aid of large scale simulations in realistic urban and highway scenarios, we provide an insight in such a comparison, also trying to isolate the contribution of the physical and medium access control layers. Full article
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<p>LTEV2Vsim block diagram.</p>
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<p>Distribution of the number of neighbours in the three scenarios.</p>
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<p>Packet reception ratio and update delay in Highway.</p>
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<p>Packet reception ratio and update delay in Bologna.</p>
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<p>Packet reception ratio and update delay in Bologna.</p>
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<p>Packet reception ratio and update delay in Cologne.</p>
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<p>Packet reception ratio vs. distance.</p>
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<p>Update delay vs. target.</p>
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16 pages, 1983 KiB  
Article
Dynamic Task Scheduling Algorithm with Deadline Constraint in Heterogeneous Volunteer Computing Platforms
by Ling Xu, Jianzhong Qiao, Shukuan Lin and Wanting Zhang
Future Internet 2019, 11(6), 121; https://doi.org/10.3390/fi11060121 - 28 May 2019
Cited by 15 | Viewed by 4393
Abstract
Volunteer computing (VC) is a distributed computing paradigm, which provides unlimited computing resources in the form of donated idle resources for many large-scale scientific computing applications. Task scheduling is one of the most challenging problems in VC. Although, dynamic scheduling problem with deadline [...] Read more.
Volunteer computing (VC) is a distributed computing paradigm, which provides unlimited computing resources in the form of donated idle resources for many large-scale scientific computing applications. Task scheduling is one of the most challenging problems in VC. Although, dynamic scheduling problem with deadline constraint has been extensively studied in prior studies in the heterogeneous system, such as cloud computing and clusters, these algorithms can’t be fully applied to VC. This is because volunteer nodes can get offline whenever they want without taking any responsibility, which is different from other distributed computing. For this situation, this paper proposes a dynamic task scheduling algorithm for heterogeneous VC with deadline constraint, called deadline preference dispatch scheduling (DPDS). The DPDS algorithm selects tasks with the nearest deadline each time and assigns them to volunteer nodes (VN), which solves the dynamic task scheduling problem with deadline constraint. To make full use of resources and maximize the number of completed tasks before the deadline constraint, on the basis of the DPDS algorithm, improved dispatch constraint scheduling (IDCS) is further proposed. To verify our algorithms, we conducted experiments, and the results show that the proposed algorithms can effectively solve the dynamic task assignment problem with deadline constraint in VC. Full article
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<p>Master-slave model.</p>
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<p>An example of task scheduling at time <span class="html-italic">l<sub>1</sub></span>. (<b>a</b>) List of tasks at time <span class="html-italic">l<sub>1</sub></span>; (<b>b</b>) list of volunteer nodes at time <span class="html-italic">l<sub>1</sub></span>; (<b>c</b>) task allocation process at time <span class="html-italic">l<sub>1</sub></span>.</p>
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<p>Task list and volunteer nodes list at time <span class="html-italic">l<sub>1</sub></span> + 1. (<b>a</b>) List of tasks at time <span class="html-italic">l<sub>1</sub></span> + 1; (<b>b</b>) list of volunteer nodes at time <span class="html-italic">l<sub>1</sub></span> + 1.</p>
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<p>The execution processes of the deadline preference dispatch scheduling (DPDS) algorithm.</p>
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<p>An example of using a risk prediction model to predict completion risk of the task. (<b>a</b>) The range of online volunteer nodes from time <span class="html-italic">l<sub>1</sub></span> to time <span class="html-italic">l<sub>1</sub></span> + 4; (<b>b</b>) list of tasks at time <span class="html-italic">l<sub>1</sub></span>; (<b>c</b>) the possible world set <span class="html-italic">W</span> of the task <span class="html-italic">t<sub>6</sub></span>.</p>
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<p>Task classification and corresponding priority.</p>
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<p>The execution processes of the improved dispatch constraint scheduling (IDCS) algorithm.</p>
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<p>The impact of the average size of the tasks on the performance of the algorithms: (<b>a</b>) The impact of average size of tasks on task completion rate; (<b>b</b>) the impact of the average size of tasks on number of the tasks completed.</p>
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<p>The impact of task set scale on the performance of the algorithms: (<b>a</b>) The impact of task set scale on task completion rate; (<b>b</b>) the impact of the task set scale on the number of tasks completed.</p>
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<p>The impact of the number of volunteer nodes on the performance of the algorithms: (<b>a</b>) The impact of the number of volunteer nodes task completion rate; (<b>b</b>) the impact of the number of volunteer nodes on the number of tasks completed.</p>
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<p>Performance comparisons of the three algorithms on the dynamic task set: (<b>a</b>) Comparison of task completion rate; (<b>b</b>) comparison of the number of tasks completed.</p>
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