Motivation and satisfaction of volunteers for community-based urban agriculture programmes

Urban agriculture means cultivating plants and raising livestock within cities for food and other uses. A Community‐based Urban Agriculture Programme is where people from residential areas get together as volunteers to practise urban agriculture in an empty space within residential areas. However, the programme encounters problems when it is incapable of attracting enough volunteers and retaining them in order to establish a sustainable programme. This study aims to determine the relationship between the dimensions of motivation and satisfaction of volunteers on the Community‐based Urban Agriculture Programme. Data collected from 375 volunteers on the Community‐based Urban Agriculture Programme in Klang Valley, Malaysia were analysed using descriptive analysis, reliability analysis, correlation analysis, and hierarchical multiple regression analysis. It was found that the most significant predictor of Community‐based Urban Agriculture Programme volunteers’ satisfaction was favoured by external factors such as campaigns, support groups, Department of Extension, and community as well as government policy, followed by love of farming, social referents, and values. Therefore, there should be a focus on the above‐mentioned dimensions of motivation in order to enhance the satisfaction of volunteers towards the Community‐based Urban Agriculture Programme

Study of optimum conversion of a hydroelectric plant into a reversible one, in managing and storing excess quantities of electrical energy

116 σ.Μελέτη βέλτιστης μετατροπής ήδη υπάρχων υδροηλεκτρικού σταθμού στον ελλαδικό χώρο σε αναστρέψιμο. Η μελέτη χωρίζεται σε δύο βασικά μέρη. Στο πρώτο μέρος προγραμματίσθηκε κώδικας Fortran που υπολόγισε τα βασικά μεγέθη του αντλιοστασίου, το νέο πρόγραμμα παραγωγής του υδροηλεκτρικού σταθμού και συγκεντρωτικά ενεργειακά και οικονομικά αποτελέσματα. Στο δεύτερο μέρος χρησιμοποιήθηκε πρόγραμμα βελτιστοποίησης εξελικτικών αλγορίθμων για την εύρεση της βέλτιστης ονομαστικής ισχύος της αντλίας και των ωρών λειτουργίας της κάθε ημέρα του έτους.Study of optimum conversion of an existing Greek hydroelectric plant, into a reversible one. The study is separated in two parts. At the first part Fortan code was programmed in order to calculate the basic variables of the pump station, the new production program of the hydroelectric plant and total energy and economical results. At the second part optimization program of evolutionary algorithms was used, so as to find the optimal named power of the pump station and the total everyday hours that it should work.Στυλιανός Σ. Γιαννουλάκη

Identifying image tags from Instagram hashtags using the HITS algorithm

Many automatic image annotation methods are based on the learning by example paradigm. Image tagging, through manual image inspection, is the first step towards this end. However, manual image annotation, even for creating the training sets, is time-consuming, complicated and contains human subjectivity errors. Thus, alternative ways for automatically creating training examples, i.e., pairs of images and tags, are crucial. As we showed in one of our previous studies, tags accompanying photos in social media and especially the Instagram hashtags can be used for image annotation. However, it turned out that only a 20% of the Instagram hashtags are actually relevant to the content of the image they accompany. Identifying those hashtags through crowdsourcing is a plausible solution. In this work, we investigate the effectiveness of the HITS algorithm for identifying the right tags in a crowdsourced image tagging scenario. For this purpose, we create a bipartite graph in which the first type of nodes corresponds to the annotators and the second type to the tags they select, among the hashtags, to annotate a particular Instagram image. From the results, we conclude that the authority value of the HITS algorithm provides an accurate estimation of the appropriateness of each Instagram hashtag to be used as a tag for the image it accompanies while the hub value can be used to filter out the dishonest annotators

The emergence of operator-neutral small cells as a strong case for cloud computing at the mobile edge

Small cells have emerged as a useful tool for supporting increased network capacity through network densification, but they can also be used to support edge cloud computing services. In this paper, we provide a preview of an innovative concept that tackles the consolidation of multi-tenancy in such type communications infrastructures, as well as the placement of network intelligence and applications in the network edge. After surveing the challenges and the enabling technologies, we present the envisaged architecture to manage and control the Cloud-Enabled Small Cell infrastructure. Also, at the operation level, we explain the potential advantages of adopting the proposed solutions on the long-term evolution access network

A Novel Architectural Concept for Enhanced 5G Network Facilities

The 5G ESSENCE project’s context is based on the concept of Edge Cloud Computing and Small Cell-as-a-Service (SCaaS) -as both have been previously identified in the SESAME 5G-PPP project of phase 1- and further “promotes” their role and/or influences within the related 5G vertical markets. 5G ESSENCE’s core innovation is focused upon the development/provision of a highly flexible and scalable platform, offering benefits to the involved market actors. The present work identifies a variety of challenges to be fulfilled by the 5G ESSENCE, in the scope of an enhanced architectural framework. The proposed technical approach exploits the profits of the centralization of Small Cell functions as scale grows through an edge cloud environment, based on a two-tier architecture with the first distributed tier being for offering low latency services and the second centralized tier being for the provision of high processing power for computing-intensive network applications. This permits decoupling the control and user planes of the Radio Access Network (RAN) and achieving the advantages of Cloud-RAN without the enormous fronthaul latency restrictions. The use of end-to-end network slicing mechanisms allows for sharing the related infrastructure among multiple operators/vertical industries and customizing its capabilities on a per-tenant basis, creating a neutral host market and reducing operational costs

A Novel Architectural Concept for Enhanced 5G Network Facilities

The 5G ESSENCE project’s context is based on the concept of Edge Cloud Computing and Small Cell-as-a-Service (SCaaS) -as both have been previously identified in the SESAME 5G-PPP project of phase 1- and further “promotes” their role and/or influences within the related 5G vertical markets. 5G ESSENCE’s core innovation is focused upon the development/provision of a highly flexible and scalable platform, offering benefits to the involved market actors. The present work identifies a variety of challenges to be fulfilled by the 5G ESSENCE, in the scope of an enhanced architectural framework. The proposed technical approach exploits the profits of the centralization of Small Cell functions as scale grows through an edge cloud environment, based on a two-tier architecture with the first distributed tier being for offering low latency services and the second centralized tier being for the provision of high processing power for computing-intensive network applications. This permits decoupling the control and user planes of the Radio Access Network (RAN) and achieving the advantages of Cloud-RAN without the enormous fronthaul latency restrictions. The use of end-to-end network slicing mechanisms allows for sharing the related infrastructure among multiple operators/vertical industries and customizing its capabilities on a per-tenant basis, creating a neutral host market and reducing operational costs

A Modern Architectural View Based upon Enhancements of the SESAME Innovative Approach

The SESAME 5G-PPP project targets innovations in three fundamental 5G areas such as the “placement” of network intelligence and applications in the network edge through NFV and cloud computing, the substantial evolution of the Small Cell concept and the consolidation of multitenancy in modern communications infrastructure. A dedicated architecture has been proposed for that purpose. In the present work and taking onto account recent challenges, we discuss latest innovations and/or potential updates of the corresponding architecture, in specific areas covering the SC-Common VNF as fun-in/fun-out module, the progress in SESAME Small Cell functional splits, the placement of “Self-x” features and wireless backhauling. Moreover, we proceed further and analyse the functional description of the related architectural components, in order to promote future improvements. Keywords—5G; Cloud-enabled Small Cell (CESC); Network Functions Virtualization (NFV); Multitenacy; “Self-x” properties; Small Cell (SC); VNF (Virtual Network Function