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991.
中国工业设计正值空前的发展机遇。“观念与认识”、“人才与机制”、“资源与共享”、“传统与创新”等诸多问题都在困扰或阻碍着工业设计的正常发展。针对创新服务模式对工业设计的促进作用,作了认真的思考,希望对工业设计的发展有所贡献。  相似文献   
992.
Cloud infrastructures consisting of heterogeneous resources are increasingly being utilized for hosting large-scale distributed applications from diverse users with discrete needs. The multifarious cloud applications impose varied demands for computational resources along with multitude of performance implications. Successful hosting of cloud applications necessitates service providers to take into account the heterogeneity existing in the behavior of users, applications and system resources while respecting the user’s agreed Quality of Service (QoS) criteria. In this work, we propose a QoS-Aware Resource Elasticity (QRE) framework that allows service providers to make an assessment of the application behavior and develop mechanisms that enable dynamic scalability of cloud resources hosting the application components. Experimental results conducted on the Amazon EC2 cloud clearly demonstrate the effectiveness of our approach while complying with the agreed QoS attributes of users.  相似文献   
993.
2017年4月12号第一颗国产高通量宽带卫星-中星16发射成功,Ka高通量宽带卫星网络在国内已经正式运行,本文就国内高通量卫星宽带业务做相应探讨。  相似文献   
994.
Aiming at previous research primarily focused on constructing service paths with a single objective,for exam-ple,latency minimization,cost minimization or load balance,which ignored the overall performance of constructed ser-vice paths,a multi-objective service path constructing algorithm based on discrete particle swarm optimization (MOPSO) was proposed.To promote the convergence rate and improve constructing performance,the criterions for selecting can-didate physical nodes and paths were explored,and a particle position initialization and update strategy (PIFC) was de-signed.Simulation experiments show that the proposed algorithms can improve the overall quality of service paths and increase the success rate and long-term average revenue.  相似文献   
995.
Cloud computing provides scalable computing and storage resources over the Internet. These scalable resources can be dynamically organized as many virtual machines (VMs) to run user applications based on a pay-per-use basis. The required resources of a VM are sliced from a physical machine (PM) in the cloud computing system. A PM may hold one or more VMs. When a cloud provider would like to create a number of VMs, the main concerned issue is the VM placement problem, such that how to place these VMs at appropriate PMs to provision their required resources of VMs. However, if two or more VMs are placed at the same PM, there exists certain degree of interference between these VMs due to sharing non-sliceable resources, e.g. I/O resources. This phenomenon is called as the VM interference. The VM interference will affect the performance of applications running in VMs, especially the delay-sensitive applications. The delay-sensitive applications have quality of service (QoS) requirements in their data access delays. This paper investigates how to integrate QoS awareness with virtualization in cloud computing systems, such as the QoS-aware VM placement (QAVMP) problem. In addition to fully exploiting the resources of PMs, the QAVMP problem considers the QoS requirements of user applications and the VM interference reduction. Therefore, in the QAVMP problem, there are following three factors: resource utilization, application QoS, and VM interference. We first formulate the QAVMP problem as an Integer Linear Programming (ILP) model by integrating the three factors as the profit of cloud provider. Due to the computation complexity of the ILP model, we propose a polynomial-time heuristic algorithm to efficiently solve the QAVMP problem. In the heuristic algorithm, a bipartite graph is modeled to represent all the possible placement relationships between VMs and PMs. Then, the VMs are gradually placed at their preferable PMs to maximize the profit of cloud provider as much as possible. Finally, simulation experiments are performed to demonstrate the effectiveness of the proposed heuristic algorithm by comparing with other VM placement algorithms.  相似文献   
996.
Research has found workplace ostracism to negatively impact workplace attitudes and behaviours such as job satisfaction, organisational citizenship behaviour, and job performance. However, research investigating beyond the direct effects of workplace ostracism and findings about boundary conditions for mitigating the negative effects of workplace ostracism are limited in organisational studies. In this regard, this study explored the mediating effects of job satisfaction on the relationship between workplace ostracism and innovative behaviour and the moderating effects of social networking services for work-related purposes for the relationship between workplace ostracism and job satisfaction. The two-wave study consisted of 237 full-time employees in large organisations in South Korea. The hierarchical regression analyses resulted in job satisfaction to mediate the relationship between workplace ostracism and innovative behaviour and social network service to significantly moderate the relationship between workplace ostracism and job satisfaction. Moreover, mediated moderation was found for the study model, which further suggests that using social network services for work-related purposes had indirect effects on innovative behaviour.  相似文献   
997.
重点介绍了如何建立机械制造业中的远程加工工况信息集成系统,这种系统大大改善加工操作的环境,提高设备利用率和灵活性以及人机一体化智能水平,通过对于数字化服务技术的远程服务思想的分析,对提高机械设备的维护具有很大意义。  相似文献   
998.
针对湿法气流床气化炉耐火材料损耗严重的问题,从块状剥落、烧蚀损伤、冲蚀损伤、化学侵蚀4方面进行了原因分析,提出可以通过合理选煤、改善工艺、合理选材及精心筑炉等手段延长耐火砖寿命。  相似文献   
999.
魏有福 《工业催化》2014,22(1):61-63
论述了制合成气过程催化剂的选择及重要性,转化催化剂要求有较好的低温活性和抗积炭性能,中变催化剂考虑催化剂本体含硫量,低变催化剂要从活性、热稳定性、堆积密度、还原后体积收缩率、烧失重和自由水含量等方面衡量,甲烷化催化剂的选用要根据设备状况满足工艺要求方面考虑。催化剂的使用寿命既与合理选用催化剂有重要关系,也与工业应用过程中的正确使用和维护有关。  相似文献   
1000.
董波 《中国机械》2014,(21):114-115
对于高炉制粉螺旋输灰机的运行原理以及对结构进行改进,使得改进后的结构不仅便于设备进行维修,节约了检修时间也降低了劳动强度,更加延长了设备的使用寿命,降低故障率,也很大程度上降低了煤粉泄漏对环境的污染。  相似文献   
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