Review of different approaches for optimal performance of multi-processors

We reviewed the literature used for optimal performance of multi-processor, we study different approaches in this paper. They include rate monotonic, deadline monotonic, and Earliest deadline first Algorithm. These approaches are basically used for real time scheduling systems .The problem of inconsistencies occurring in these algorithms such as those tasks whose task period is less but if not executed does not matter and whenever they are scheduled under rate monotonic scheduling algorithm the time consumed by CPU in scheduling the tasks is spent unnecessarily

Formal and Executable Specification of Random Waypoint Mobility Model Using Timed Coloured Petri Nets for WMN

The wireless mesh network (WMN) is an emerging and cost-effective alternative paradigm for the next generation wireless networks in many diverse applications. In the performance evaluation of routing protocol for the WMN, it is essential that it should be evaluated under realistic conditions. The usefulness of specific mobility protocol can be determined by selection of mobility model. This paper introduces a coloured Petri nets (CP-nets) based formal model for implementation, simulation, and analysis of most widely used random waypoint (RWP) mobility model for WMNs. The formal semantics of hierarchical timed CP-nets allow us to investigate the terminating behavior of the transitions using state space analysis techniques. The proposed implementation improves the RWP mobility model by removing the “border effect” and resolves the “speed decay” problem

Module-based architecture for a periodic job-shop scheduling problem

AbstractThis paper addresses the Petri net (PN) based design and modeling approach for a periodic job-shop scheduling problem. Asynchronous synthesis for net-modules of the jobs is suggested in this paper for optimal allocation of shared resources to different operations. To make sure the completion of all the jobs in a single iteration of a production cycle and the correct calculation of a makespan, the synchronization problem among jobs is tackled by introducing the special synchronizing transition in the model. A timed-place PN is adopted for the purpose of finding the feasible schedule in terms of the firing sequence of the transitions of the PN model by using the heuristic search method. Further, the characterization of the PN model is performed and it is shown that the PN model for a periodic job-shop scheduling problem is equivalent to a class of PN known as parallel process net with resources (PPNRs). The modeling approach is demonstrated with a practical example and a makespan is calculated for the example

Competence of Benzoil Tree (Moringa Oleifera L.) as Antibacterial and Antifungal Agent

Background: A plant’s activity towards biological properties is the first step to consider it for medicinal and therapeutic purposes. To evaluate the medicinal properties, we have determined the anti-bacterial and anti-fungal potential of Moringa oleifera L. (Benzoil tree). The focus was to obtain and isolate certain chemical substances that can neutralize the effect of common and pathogenic selected bacterial and fungal species collected from local hospitals of Khyber Pakhtunkhwa.Methods: A total of five fractions were selected i.e. crude methanolic extracts, n-hexane, chloroform, ethyl acetate and aqueous extracts were prepared and their activity checked against four bacterial strains including Streptococcus mutans, Staphylococcus aurous, MRSA (methicillin resistance Staphylococcus aurous) and Serratia marcescens; and four fungal strains i.e. Fusarium oxysporum, Aspergillus flavus, Polysphondylium pallidum and Alternaria alternata.Results: The highest anti-bacterial activity shown by crude methanolic extract fraction i.e. (48-38%) and the lowest activity was exhibited by aqueous extract (15-0%) against all the selected bacterial strains. Similarly, the highest anti-fungal activity indicated by crude methanolic extracts (60-45%) against the four selected fungal species and lowest activity shown by the aqueous fractions (26-0%). Reasonable activity was also exhibited by others fractions as well.Conclusion: The outcomes of our experiment strongly supports that Moringa oleifera has significant antibacterial and antifungal activities, so the plant is effective antibacterial and antifungal agent.Keywords: Benzoil tree; Moringa oleifera; Antibacterial; Antifungal; Drum stick Tre

Optimum spacing between grooved tubes: an experimental study

An experimental study on the optimum spacing between grooved tubes is reported in this paper. Two grooved tubes having a pitch of 10 mm and 15 mm and a plain tube were considered for the heat transfer analysis. The spacing between two tubes with the same pitch was varied from 10 mm to 35 mm with a step size of 5 mm. The velocity of air flowing over the tube surfaces was changed from 0.4 m/s to 1 m/s using a blower fan. Based on Nusselt number (Nu) the optimum spacing between the tubes was decided. The optimum spacing between grooved tubes of pitch 10 mm and 15 mm was compared with that of plain tubes. From the experimental analysis, it was noticed that with an increase in air velocity (increase in Reynolds number) the tube surface temperature reduced irrespective of any tube considered. Nu increased with an increase in air velocity for all the tubes. The important conclusion drawn from the present study was that there exists a limiting spacing (optimum) between the tubes above which no change in Nu was observed. The spacing of 30 mm was found to be the optimum spacing between the tubes irrespective of its surface geometry modifications