2 research outputs found

    Comparison of the Execution Step Strategies on Scheduling Data-intensive Workflows on IaaS Cloud Platforms

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    The IaaS platforms of the Cloud hold promise for executing parallel applications, particularly data-intensive scientific workflows. An important challenge for users of these platforms executing scientific workflows is to strike the right trade-off between the execution time of the scientific workflow and the cost of using the platform. In a previous article, we proposed an efficient approach that assists the user in finding this compromise. This approach requires an algorithm aimed at minimizing the execution time of the workflow once the platform configuration is set. In this article, we compare two different strategies for executing a workflow after its offline scheduling using an algorithm. The algorithm that we proposed in the previous study has outperform the HEFT algorithm. The first strategy allows some ready tasks to execute earlier than other higher-priority tasks that are ready later due to data transfer times. This strategy is justified by the fact that although our scheduling algorithm attempts to minimize data transfers between tasks running on different virtual machines, this algorithm does not include data transfer times in the planned execution dates for the various tasks of the workflow. The second strategy strictly adheres to the predetermined order among tasks scheduled on the same virtual machine. The results of our evaluations show that the best execution strategy depends on the characteristics of the workflow. For each evaluated workflow, our results demonstrate that our scheduling algorithm combined with the best execution strategy surpasses HEFT. The choice of the best strategy must be determined experimentally following realistic simulations, such as the ones we conduct here using the WRENCH framework, before conducting simulations to find the best compromise between cost and execution time of a workflow on an IaaS platform.

    Success factors affecting the healthcare professionals to utilize cloud computing services

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    Integrating the new technologies to improve the healthcare services can be seen as one of the research trends nowadays, as earlier studies have recommended the potential of emerging technologies in enhancing healthcare service practices by means of providing more opportunities to carry out activities essential for prevention, diagnosis, monitoring, and treatment of the disease. Involving the cloud computing services in healthcare domain can offer a way for handling and maintaining health data by making use of software applications hosted on the Internet. To ensure successful cloud computing utilization, a pre-examination on the context of usage should be applied in order to collect the real needs to guarantee getting all the possible benefits of this technology. In Iraq, the health records of public hospitals consist of various types of data which continue to increase in velocity, volume, and variety progressively. This has led to several major issues to the health sectors from two perspectives, data complexity and low IT integrity. For that reason, managing and maintaining all these health data are essential to healthcare organizations. In this paper, we collected the success factors that may influence the healthcare professionals to utilize cloud computing services for the health sector in Iraq. This is done by conducting an interview with 30 physicians and technicians from four hospitals in Iraq, then a literature survey was carried out to verify that all the gathered factors are within the circumstance of healthcare. It has been found that eight factors may affect the perspective of healthcare professionals to utilize cloud computing services. Finally, a conceptual model was developed based on the findings
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