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In this paper, the idea of omitting the recovery time when it is too short that it can be considered as negligible is incorporated in a software rejuvenation model. Two new models are introduced, in which the instantaneous availability is defined when firstly the rejuvenation time and secondly both rejuvenation and repair times can be omitted. The main purpose consists in regarding system software as operational when the time spent in a non-operational state, like the rejuvenation and the failure states, does not exceed a predefined time threshold. By modeling the evolution of such a software rejuvenation model using continuous-time Markov chains, we define its availability depending on whether the rejuvenation and the repair critical times are constant or random variables. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Software rejuvenation is modeled in a client-server system, which provides resources to priority classes of users. To assure availability, resource reservation policies are adopted for the higher priority classes. In addition software rejuvenation is proposed to optimize resource availability. The system is modeled by a cyclic nonhomogeneous Markov chain to capture the variation of the arrival and service rates during a day period. An optimization problem is solved based on a similar previous work and given the optimal resource reservation policy obtained by its solution, rejuvenation is performed and the optimal rejuvenation policy is determined. As a measure of resource availability the blocking probability of each priority class is used. Performability indicators expressing the total cost are also derived, with respect to the optimal resource reservation and optimal rejuvenation policies, to examine whether rejuvenation benefits the system in terms of cost. To derive the blocking probabilities, the limiting probability distribution is computed using explicit generalized approximate inverse preconditioning for solving efficiently sparse linear systems of algebraic equations. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Human rights education has an encouraging effect on children's school routine. The aim of the present study was to investigate the effectiveness of a 12-session transformative human rights education intervention in improving children's school adjustment. Participants were 340 Greek primary school students assigned to intervention group (n = 187) and control group (n = 153). All members completed a written questionnaire 1 week before the implementation of the intervention, measuring their knowledge of human rights, school engagement, perceptions of the school environment, interpersonal relationships, empathy and perceptions, attitudes and feelings towards school. The completion process of the same questionnaire was repeated 1 week after the termination of the intervention and 4 months later. The results showed that the intervention was particularly beneficial as the intervention group members demonstrated a significant increase in their knowledge of human rights, school engagement, perceptions of the school environment, empathy and school liking, while experiencing a significant decrease in school avoidance and loneliness. Members of the control group did not report any significant improvement over time. The study's implications for future research on school-based human rights interventions are discussed., (© 2023 The Authors. International Journal of Psychology published by John Wiley & Sons Ltd on behalf of International Union of Psychological Science.)

The distribution of parcels is one of the most complex and challenging processes in supply chain execution. Lately, the development of both electronic and quick commerce has driven carriers and courier operators to identify more effective methods for express parcel delivery. To this end, the development of efficient distribution networks that aim in increasing customer experience while maintaining low operating costs is significant importance both for researchers as well as for practitioners. This article presents a dataset for the Van Drone Routing Problem with Multiple Delivery Points and Cooperation (VDRPMDPC). The latter examines a van-drone team from an operational viewpoint, where a van moves along a road network while the drone egress and ingress from a van to a nearby delivery location and then travels back to the van. This problem has been created with the aim of assessing the design of more sustainable and cost-effective delivery routes in urban and semi urban environments via the use of Unmanned Aerial Vehicles (UAVs). For the development of this dataset real geographical positions have been used located at two different areas of Athens, Greece. The entire benchmark is composed of 14 instances comprised by 20, 40, 60 and 100 clients respectively. The dataset is publicly available for its use and modification., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (© 2023 The Author(s).)

Background: Ascorbic acid (vitamin C), administered orally in high doses has been observed to relieve pain and reduce opioid use in cancer patients. In vitro studies have also shown that antioxidants, such as vitamin C, may, at high concentrations, inhibit the endogenous opioid degrading metalloenzyme and increase endorphin levels. In the present study the effects of oral administration of high doses of vitamin C on withdrawal syndrome of heroin abusers were investigated., Materials and Patients: Ascorbic acid at doses of 300 mg/kg b.w/day, supplemented with vitamin E (5 mg/kg b.w/day), was orally administered in two groups of heroin addict subjects consisting of in-patients (Group A, 30 males) and one of out-patients(Group B, 10 males), for a minimum of 4 weeks. The group A in-patients were also administered the conventional (diazepam + analgesic) medication. The results on the intensity of withdrawal syndrome (WS), estimated according to DMS-III criteria, were compared to a third group of heroin addict in-patients (group C, 30 males-control group), treated only by conventional medication., Results: The patients of the vitamin C-treated groups (in-patients and out-patients) experienced mild WS (in 46.6% to 50% of the subjects) in contrast to the control group patients, who experienced mild WS in 6.6% of the cases. The vitamin C-treated subjects expressed major WS ranging from 10% to 16.6%, in contrast to the untreated subjects (control group), who expressed a major WS in 56.6% of the cases., Conclusions: The results indicate that high doses of ascorbic acid administered orally, may ameliorate the withdrawal syndrome of heroin addicts. Further studies are needed in order to estimate the dose- and time-dependent effects of ascorbic acid treatment, and to clarify its mechanisms of action in the withdrawal syndrome.