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1.
任务卸载是雾计算的主要技术之一,即计算能力不足的节点将任务卸载给具有富余资源的节点帮助计算。以优化任务平均卸载时延和提升卸载服务成功率为目标,利用多臂老虎机理论为动态雾计算网络提出一种基于在线学习的任务卸载算法,可实时做出最优卸载决策。将该算法扩展到非稳定网络状态,使之可以动态追踪网络中节点的资源与环境变化,实时调整卸载决策。详细分析所提出算法的性能、复杂度和存储占用情况。仿真结果表明,这两种算法可达到的长期平均任务卸载时延均十分接近理想算法下的最优时延,卸载服务成功率也得到显著提升。此外,所提算法在非稳定的网络状态下能够追踪到计算资源与环境的变化。  相似文献   
2.
ABSTRACT

Background and Context

Sports and technology are often pitted as being at odds with one another. While there are several educational activities that make reference to sports we seldom see sports used as an authentic context for learning computing.  相似文献   
3.
为充分发掘分布在不同位置上的雾节点的计算资源,任务卸载被寄予众望。在雾计算场景下,以尽可能减少任务卸载的长期成本为目标,试图寻找一个高效的在线任务卸载方法。为此,这一问题被建模成一个随机规划问题,该问题中系统参数所对应的随机变量的期望会在未知时刻突变,系统参数相关信息只能在任务完成后的反馈中获得。基于非稳态多臂老虎机模型,提出一个高效的算法来解决这一具有挑战性的随机优化问题,给出理论分析证明该算法的渐进最优性。数值实验证明了该算法的优越性。  相似文献   
4.
Organizations face increasing pressure to implement artificial intelligence (AI) within a variety of business processes and functions. Many perceived benefits surround AI, but a considerable amount of trepidation also exists because of the potential of AI to replace human employees and dehumanize work. Questions regarding the future of work in the age of AI are particularly salient in pre-adoption organizations, before employees have the opportunity to gain direct experience with AI. To cope with this potentially stressful situation, employees engage in cognitive appraisal processes based on their own knowledge and personal use of AI. These pre-adoptive appraisals of AI influence both affective and cognitive attitudes, which in turn trigger behavioral responses that influence an organization’s ability to leverage AI successfully. Our survey of 363 Taiwanese employees shows that perceptions of AI’s operational and cognitive capabilities are positively related to affective and cognitive attitudes toward AI, while concerns regarding AI have a negative relationship with affective attitude only. Interaction effects of employee knowledge and affective attitude are also observed. This work’s main contribution lies in the development of an empirically-tested model of the potential impact of AI on organizations from an employee perspective in the pre-adoption phase. These results have practical implications for how organizations prepare for the arrival of this transformative technology.  相似文献   
5.
This paper presents a systematic approach to develop a resilient software system which can be developed as emerging services and analytics for resiliency. While using the resiliency as a good example for enterprise cloud security, all resilient characteristics should be blended together to produce greater impacts. A framework, cloud computing adoption framework (CCAF), is presented in details. CCAF has four major types of emerging services and each one has been explained in details with regard to the individual function and how each one can be integrated. CCAF is an architectural framework that blends software resilience, service components and guidelines together and provides real case studies to produce greater impacts to the organizations adopting cloud computing and security. CCAF provides business alignments and provides agility, efficiency and integration for business competitive edge. In order to validate user requirements and system designs, a large scale survey has been conducted with detailed analysis provided for each major question. We present our discussion and conclude that the use of CCAF framework can illustrate software resilience and security improvement for enterprise security. CCAF framework itself is validated as an emerging service for enterprise cloud computing with analytics showing survey analysis.  相似文献   
6.
We investigated whether the valence of performance feedback provided after a task, would affect participants’ perceptions of how much mental effort they invested in that same task. In three experiments, we presented participants with problem-solving tasks and manipulated the presence and valence of feedback between conditions (no, positive, or negative feedback valence), prior to asking them to rate how much mental effort they invested in solving that problem. Across the three experiments–with different problem-solving tasks and participant populations–we found that subjective ratings of effort investment were significantly higher after negative than after positive feedback; ratings given without feedback fell in between. These findings show that feedback valence alters perceived effort investment (possibly via task perceptions or affect), which can be problematic when effort is measured as an indicator of cognitive load. Therefore, it seems advisable to measure mental effort directly after each task, before giving feedback on performance.  相似文献   
7.
Learning from direct instruction can be enhanced by preparatory invention tasks: students invent an index that allows to differentiate a set of cases regarding important aspects (self-regulated). However, contradictory results have been found. As self-regulated activities often need practice, we tested whether the contradictory findings persist when students can practice inventing. We randomly assigned 99 eighth-grade students to two conditions (independent variable): they either invented twice (self-regulated; n = 49) or worked through worked solutions of the two tasks (guided; n = 50) before learning about ratios in physics from a lecture. Extraneous load, deep-structure recall, knowledge-gap perception, and self-efficacy were potential mediators. Transfer was the dependent measure. Guidance led to less extraneous load. However, self-regulation led to higher transfer because the students devoted more attention to the deep structure of the preparation tasks. Our findings suggest that—given some practice—self-regulated outperforms guided preparation for learning from direct instruction.  相似文献   
8.
Bridging schools and communities has been a goal, if not hurdle, for reformers who aim to improve the education of low-income and underrepresented students from the bottom-up. Strategies to create these connections are often characterized as ‘brokerage’, where individuals or organizations bridge two or more social worlds. This paper details the design and implementation of educational technologies that support the brokering of school–community connections using a ‘culturally responsive computing’ (CRC) framework. Culturally responsive education is often limited to content and learning styles, which misses the opportunities it creates for a brokerage process that also connects to education-based social movements for economic access in underrepresented communities. This paper provides empirical support for the claim that the CRC framework is well suited for both purposes. It allows schools and communities to build assets together, translating the knowledge and skills of underrepresented communities into math and computing education, while illuminating the ways in which technologies can motivate education-based social movement building.  相似文献   
9.
对英语教学来说,词汇教学既是核心又是难点.掌握一定的词汇量是学生熟练运用英语的先决条件.本文将借助认知语言学的范畴化、原型理论和隐喻概念来探讨外语教学中词汇教学的新的有效途径.  相似文献   
10.
国外教师认知能力发展研究述评   总被引:8,自引:0,他引:8  
本文从选择注意、知觉和思维能力角度综述了国外教师认知能力发展的研究现状并分析和讨论了该领域研究对师范教育与教师培训的意义.  相似文献   
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