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971.
We have proposed the use of autonomous agents for coping with some of the challenges of creating ambient computing systems. The motivation of this research is that ambient computing environments are characterized by the distribution, reactivity, collaboration and adaptation of their artifacts, which are also characteristics attributed to software agents. To assist developers in creating the software entities of an ambient computing environment, the Simple Agent Library for Smart Ambients (SALSA) was created. The SALSA middleware and architecture enables the creation of autonomous agents reactive to the context of the ambient computing environment. SALSA agents can represent users, resources, or wrap complex system functionality of the environment. The aim of this paper is to provide evidence that SALSA facilitates the implementation of ambient computing services through autonomous agents. Unfortunately, the literature on Ubicomp development frameworks has, aside from a few exceptions, not reported experimental evaluation of their usability. The evaluations of Ubicomp development platforms have not addressed this issue since their evaluations have been mostly focused on performance and to prove feasibility. We present the results of an empirical evaluation conducted to assess the use of SALSA. This study included in-lab programming experiments and design exercises to evaluate the programming facilities provided by SALSA agents. Even though for some of the evaluation participants the use of autonomous agents as an abstraction for the development of ubiquitous computing systems was not innate, the evaluation results demonstrate that the execution model of SALSA and its facilities to implement Ubicomp systems are comprehensible. 相似文献
972.
Cloud brokering mechanisms for optimized placement of virtual machines across multiple providers 总被引:1,自引:0,他引:1
Johan TordssonAuthor Vitae Rubén S. MonteroAuthor Vitae 《Future Generation Computer Systems》2012,28(2):358-367
In the past few years, we have witnessed the proliferation of a heterogeneous ecosystem of cloud providers, each one with a different infrastructure offer and pricing policy. We explore this heterogeneity in a novel cloud brokering approach that optimizes placement of virtual infrastructures across multiple clouds and also abstracts the deployment and management of infrastructure components in these clouds. The feasibility of our approach is evaluated in a high throughput computing cluster case study. Experimental results confirm that multi-cloud deployment provides better performance and lower costs compared to the usage of a single cloud only. 相似文献
973.
Distributed computing for carbon footprint reduction by exploiting low-footprint energy availability
Ward Van HeddeghemAuthor Vitae Willem VereeckenAuthor VitaeDidier ColleAuthor Vitae Mario PickavetAuthor VitaePiet DemeesterAuthor Vitae 《Future Generation Computer Systems》2012,28(2):405-414
Low carbon footprint energy sources such as solar and wind power typically suffer from unpredictable or limited availability. By globally distributing a number of these renewable sources, these effects can largely be compensated for. We look at the feasibility of this approach for powering already distributed data centers in order to operate at a reduced total carbon footprint. From our study we show that carbon footprint reductions are possible, but that these are highly dependent on the approach and parameters involved. Especially the manufacturing footprint and the geographical region are critical parameters to consider. Deploying additional data centers can help in reducing the total carbon footprint, but substantial reductions can be achieved when data centers with nominal capacity well below maximum capacity redistribute processing to sites based on renewable energy availability. 相似文献
974.
Jianxin LiAuthor Vitae Bo LiAuthor Vitae K.P. LamAuthor Vitae 《Future Generation Computer Systems》2012,28(2):379-390
As the sizes of IT infrastructure continue to grow, cloud computing is a natural extension of virtualisation technologies that enable scalable management of virtual machines over a plethora of physically connected systems. The so-called virtualisation-based cloud computing paradigm offers a practical approach to green IT/clouds, which emphasise the construction and deployment of scalable, energy-efficient network software applications (NetApp) by virtue of improved utilisation of the underlying resources. The latter is typically achieved through increased sharing of hardware and data in a multi-tenant cloud architecture/environment and, as such, accentuates the critical requirement for enhanced security services as an integrated component of the virtual infrastructure management strategy. This paper analyses the key security challenges faced by contemporary green cloud computing environments, and proposes a virtualisation security assurance architecture, CyberGuarder, which is designed to address several key security problems within the ‘green’ cloud computing context. In particular, CyberGuarder provides three different kinds of services; namely, a virtual machine security service, a virtual network security service and a policy based trust management service. Specifically, the proposed virtual machine security service incorporates a number of new techniques which include (1) a VMM-based integrity measurement approach for NetApp trusted loading, (2) a multi-granularity NetApp isolation mechanism to enable OS user isolation, and (3) a dynamic approach to virtual machine and network isolation for multiple NetApp’s based on energy-efficiency and security requirements. Secondly, a virtual network security service has been developed successfully to provide an adaptive virtual security appliance deployment in a NetApp execution environment, whereby traditional security services such as IDS and firewalls can be encapsulated as VM images and deployed over a virtual security network in accordance with the practical configuration of the virtualised infrastructure. Thirdly, a security service providing policy based trust management is proposed to facilitate access control to the resources pool and a trust federation mechanism to support/optimise task privacy and cost requirements across multiple resource pools. Preliminary studies of these services have been carried out on our iVIC platform, with promising results. As part of our ongoing research in large-scale, energy-efficient/green cloud computing, we are currently developing a virtual laboratory for our campus courses using the virtualisation infrastructure of iVIC, which incorporates the important results and experience of CyberGuarder in a practical context. 相似文献
975.
976.
977.
介绍了云计算与物联网的主要技术特点,阐述了两种技术在供应链管理中的应用,最后指出了应用该技术需要注意的问题及实现技术带来的价值。 相似文献
978.
基于云计算的医疗信息系统研究 总被引:1,自引:0,他引:1
探讨了多地、异构的医疗卫生机构信息管理数据迁移到云平台上集中管理、应用的实施方案,通过云计算环境,对现有的医疗信息进行联机管理、集成与共享,以实现信息资源的共享,构建医疗信息的共享平台,实现医疗设备、医务人员、医疗机构之间的大范围、多层次互动,实现跨地域、跨学科、多模式的医疗数据的整合与共享,以此实现医疗数据的最优整合和最大协同效应. 相似文献
979.
采用词汇测试与访谈相结合的方法探讨了3G与云计算环境下大学英语词汇自主学习效果。结果显示,3G与云计算环境下,基于智能移动设备的自主学习对提高大学生的词汇量以及词汇运用能力都有显著作用。这主要因为,基于3G和云计算技术构建英语词汇自主学习平台,学习者利用智能移动设备可以随时、随地、随身在真实自然语境中学习和活用词汇,再加上学习过程中与教师和其他学习者的实时交互和协作,其词汇学习的效率与质量有了大幅提高。 相似文献
980.