528 research outputs found

    Social-Aware Forwarding Improves Routing Performance in Pocket Switched Networks

    Get PDF
    Several social-aware forwarding strategies have been recently introduced in opportunistic networks, and proved effective in considerably in- creasing routing performance through extensive simulation studies based on real-world data. However, this performance improvement comes at the expense of storing a considerable amount of state information (e.g, history of past encounters) at the nodes. Hence, whether the benefits on routing performance comes directly from the social-aware forwarding mechanism, or indirectly by the fact state information is exploited is not clear. Thus, the question of whether social-aware forwarding by itself is effective in improving opportunistic network routing performance remained unaddressed so far. In this paper, we give a first, positive answer to the above question, by investigating the expected message delivery time as the size of the net- work grows larger

    Knowledge Management & Loyalty Programs: A Customer Perception Analysis, the Greek Retail Market

    Get PDF
    The Food Retail sector in Greece is currently facing a number of challenges. From an economic point of view, the austerity programs imposed in Greece since 2010 resulted in losses of retail sales, alongside with bankruptcies and mergers of retail chains. At the same time, technological development creates an environment for innovation in terms of operations and marketing and offers new opportunities to retailers. Additionally, consumers become more involved and active in the purchasing processes. However, Greek consumers are also experiencing a dramatic decline in their disposable income. The study examines the perception of Greek consumers of several marketing efforts based on Information & Communication Technology Systems (ICT) introduced by a Greek food retailer in Northern Greece. More specifically, it investigates the relationship between ICT related marketing efforts, such as loyalty programs, and analytics regarding food control systems and purchases and consumer characteristics such as gender, age, income, status and family size. The study reveals a number of relationships between marketing efforts and consumer characteristics/segments. However, since the relationships are found to be weak, marketing managers are advised to use advanced analytics systems, such as big data technologies, in order to enhance the efficiency of their marketing strategies and approaches. The weak relationships between the parameters examined indicate that marketing efforts have to focus in several consumer sub segments in order to achieve significant results. The study’s sample population is consumers of one of the top food retailers in Greece. The findings contribute to the literature on the use of ICT on marketing strategies and the use of big data. Furthermore, they have practical implications for marketers in the retail food sector, as they reveal the need for a more focused approach to different consumer groups, in order to increase the efficiency of marketing efforts and to achieve maximum results.     Keywords: knowledge management, loyalty programs, ICT, segmentatio

    Limit overturning moment chuck

    Get PDF
    Limited memory capacity is one of the major constraints in Delay Tolerant Wireless Sensor Networks. Efficient management of the memory is critical to the performance of the network. This paper proposes a novel buffer management algorithm, SmartGap, a Quality of Information (QoI) targeted buffer management algorithm. That is, in a wireless sensor network that continuously measures a parameter which changes over time, such as temperature, the value of a single packet is governed by an estimation of its contribution to the recreation of the original signal. Attractive features of SmartGap include a low computational complexity and a simplified reconstruction of the original signal. An analysis and simulations in which the performance of SmartGap is compared with the performance of several commonly used buffer management algorithms in wireless sensor networks are provided in the paper. The simulations suggest that SmartGap indeed provides significantly improved QoI compared the other evaluated algorithms.QC 20150605</p

    Ethnic differences in thromboprophylaxis for COVID-19 patients: should they be considered?

    Get PDF
    © 2021, Japanese Society of Hematology. Thromboembolic events contribute to morbidity and mortality in coronavirus disease 2019 (COVID-19). As a result, thromboprophylaxis using low-molecular-weight heparin (LMWH) is universally recommended for hospitalized patients based on multiple guidelines. However, ethnic differences with respect to thrombogenicity have been reported and the incidence of thromboembolic events is considered to be lower in the Asian population. Despite the importance of thromboprophylaxis, bleeding is also a side effect that should be considered. We examine the data relating to potential ethnic differences in thrombosis and bleeding in COVID-19. Although sufficient data is not yet available, current evidence does not oppose routine anticoagulant use and thromboprophylaxis using a standard dose of LMWH for admitted patients regardless of ethnicity based on our review

    Physico-chemical, antimicrobial and antioxidant properties of gelatin-chitosan based films loaded with nanoemulsions encapsulating active compounds

    Get PDF
    The aim of this research was to develop and characterize gelatin-chitosan (4:1) based films that incorporate nanoemulsions loaded with a range of active compounds; N1: canola oil; N2: α-tocopherol/cinnamaldehyde; N3: α-tocopherol/garlic oil; or N4: a-tocopherol/cinnamaldehyde and garlic oil. Nanoemulsions were prepared in a microfluidizer with pressures ranging from 69 to 100 MPa, and 3 processing cycles. Films were produced by the casting method incorporating 5 g N1,2,3,4/100 g biopolymers and using glycerol as a plasticizer, and subsequently characterized in terms of their physico-chemical, antimicrobial and antioxidant properties. No differences (p > 0.05) were observed for all films in terms of moisture content (18% w/w), and thermal properties. The films' solubility in water and light transmission at 280 nm were considerably reduced as compared to the control, N1 (15% and 60% respectively) because of the nanoemulsion incorporation. The film loaded with N1 showed the greatest (p < 0.05) opacity, elongation at break and stiffness reduction, and was the roughest, whilst the lowest tensile strength and ability to swell were attained by films loaded with N3 and N4, respectively. DSC and X-ray analyses suggested compatibility among the biopolymeric-blend, and a good distribution of nanodroplets embedded into the matrix was confirmed by AFM and SEM analyses. Films loaded with nanoencapsulated active compounds (NAC) were very effective against Pseudomonas aeruginosa, and also showed high antioxidant activity. Overall, the present study offers clear evidence that these active-loaded films have the potential to be utilized as packaging material for enhancing food shelf life
    corecore