动态雾计算网络中基于在线学习的任务卸载算法     

谭友钰  陈蕾  周明拓  王昆仑  杨旸  张武雄 《中国科学院大学学报》2020,37(5):688-698

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   

Motivation counteracts fatigue-induced performance decrements in soccer passing performance     

Jeroen C.M. Barte  Arne Nieuwenhuys  Sabine A.E. Geurts  Michiel A.J. Kompier 《Journal of sports sciences》2019,37(10):1189-1196

Recent theories suggest that negative effects of fatigue on performance are determined by perception of effort and motivation rather than being directly caused by reaching physiological limits. In the current experiment, the influence of motivation on fatigue-induced decrements in soccer performance was experimentally investigated. Sixty amateur soccer players performed a validated soccer-passing test before and after a fatigue protocol. Results showed that players’ motivation and performance decreased after the fatigue protocol for players in the control group. In contrast, players in the motivation group (i.e., with motivation experimentally induced after the fatigue protocol) were able to uphold their motivation and increase their performance. These results indicate that motivation plays a crucial role in performance under fatigue, as fatigue-induced decrements in soccer passing performance can be counteracted by high levels of motivation. Future research may explore the limits of this counteracting effect and extend findings to other relevant performance aspects.  相似文献   

Hot hands,cold feet? Investigating effects of interacting constraints on place kicking performance at the 2015 Rugby Union World Cup     

Chris Pocock  Neil E. Bezodis  Keith Davids  Jamie S. North 《European Journal of Sport Science》2018,18(10):1309-1316

Place kicks in Rugby Union present valuable opportunities to score points outside the spatiotemporal dynamics of open play but are executed under varying performance constraints. We analysed effects of specific task constraints and relevant contextual factors on place kick performance in the 2015 Rugby Union World Cup. Data were collected from television broadcasts for each place kick. In addition to kick outcomes, contextual factors, including time of the kick in the match, score margin at the time of the kick, and outcome of the kicker’s previous kick, were recorded. Effects of spatial task constraints were analysed for each kick, using distance (m) and angle (°) of the kick to the goalposts. A binomial logistic regression model revealed that distance from, and angle to, the goalposts were significant predictors of place kick outcome. Furthermore, the success percentage of kickers who missed their previous kick was 7% lower than those who scored their previous kick. Place kick success percentage in the 10 minutes before half-time was 8% lower than the mean tournament success percentage, which was 75% (95% CI 71–78%). The highest kick success percentage was recorded when scores were level (83%; 95% CI 72–91%). Our data highlighted how subtle changes in task constraints and contextual factors can influence performance outcomes in elite performers in international competition. Fluctuations in place kick success suggested that individual constraints, such as thoughts, emotions and fatigue, induced during competition, could interact with perceptions to influence emergent performance behaviours.  相似文献   

非稳态雾赋能网络中的在线任务卸载方法     

朱兆伟  刘婷  钱骅  罗喜良 《中国科学院大学学报》2020,37(5):699-707

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   

企业信息资源配置的评价指标体系研究   总被引：5，自引：0，他引：5  

任全娥 《情报理论与实践》2006,29(5):556-558,573

本文通过对国内外学者在信息资源配置的评价指标体系与评估方法方面的相关研究成果进行全面考察分析，探讨了我国在企业信息资源配置的评价指标体系设置中存在的问题。  相似文献   

组织支持认知与领导—成员交换对员工回报的影响实证研究   总被引：3，自引：0，他引：3  

吴继红 《软科学》2006,20(5):63-66

根据组织支持认知(Perce ived O rgan izational Support)和领导—成员交换(LeaderM ember Exchange)的研究,员工既与组织也与主管建立了社会交换关系。在借鉴国内外的相关理论的基础上,通过100对主管和员工的问卷调查验证了企业员工的组织支持认知对他们的任务绩效、组织公民行为和组织承诺有正向的影响;而企业员工的领导—成员交换认知对他们的组织公民行为有正向的影响。  相似文献   

Optimization and Its Alternative in Media Choice: A Model of Reliance on Social-Influence Processes     

Bairj Donabedian Associate Professor 《The Information Society》2006,22(3):121-135

In the reconciliation of rational-choice and social-influence approaches to media choice offered here, the choice process is decomposed into two subprocesses. In the first subprocess—that of rational choice—decisional ambiguity frustrates complete optimization. Optimization is partial, yielding a set of effectively interchangeable media alternatives over which the user is indecisive. In the second subprocess—that of social influence—imitation, deference, and other cues act on the set of interchangeables, yielding a single ultimate choice. If in the social-influence subprocess there are benefits to coordinating with others, group choice crystallizes around a single media alternative. If these benefits are absent, individual choice remains idiosyncratic, with each decision maker making random choices within the set of interchangeables. In organizational life, media choice transpires sequentially, with each choice conditioning a succeeding one. In its dynamic form, the present model explicitly incorporates such sequential environments: The twofold choice process transpires iteratively within individual decision sites (in the multiple purchasing decisions of a committee, for example) and sequentially across decision sites (from committee to individual, for example). The model generates considerable empirical implications. As decisional ambiguity grows, the rational-choice component of the choice process shrinks, implying upper-bound conditions for the explanatory power of rational-choice statistical models.  相似文献   

Trusting Virtual Trust   总被引：2，自引：0，他引：2  

Paul?B.?de?LaatEmail author 《Ethics and Information Technology》2005,7(3):167-180

Can trust evolve on the Internet between virtual strangers? Recently, Pettit answered this question in the negative. Focusing on trust in the sense of ‘dynamic, interactive, and trusting’ reliance on other people, he distinguishes between two forms of trust: primary trust rests on the belief that the other is trustworthy, while the more subtle secondary kind of trust is premised on the belief that the other cherishes one’s esteem, and will, therefore, reply to an act of trust in kind (‘trust-responsiveness’). Based on this theory Pettit argues that trust between virtual strangers is impossible: they lack all evidence about one another, which prevents the imputation of trustworthiness and renders the reliance on trust-responsiveness ridiculous. I argue that this argument is flawed, both empirically and theoretically. In several virtual communities amazing acts of trust between pure virtuals have been observed. I propose that these can be explained as follows. On the one hand, social cues, reputation, reliance on third parties, and participation in (quasi-) institutions allow imputing trustworthiness to varying degrees. On the other, precisely trust-responsiveness is also relied upon, as a necessary supplement to primary trust. In virtual markets, esteem as a fair trader is coveted while it contributes to building up one’s reputation. In task groups, a hyperactive style of action may be adopted which amounts to assuming (not: inferring) trust. Trustors expect that their virtual co-workers will reply in kind while such an approach is to be considered the most appropriate in cyberspace. In non-task groups, finally, members often display intimacies while they are confident someone else ‘out there’ will return them. This is facilitated by the one-to-many, asynchronous mode of communication within mailing lists.  相似文献   

Using iPad tablets for self‐modeling with preschoolers: Videos versus photos          下载免费PDF全文

Dacia M. McCoy  Julie Q. Morrison  Dave W. Barnett  Hilary D. Kalra  Lauren K. Donovan 《Psychology in the schools》2017,54(8):821-836

As technology becomes more accessible and acceptable in the preschool setting, teachers need effective strategies of incorporating it to address challenging behaviors. A nonconcurrent delayed multiple baseline design in combination with an alternating treatment design was utilized to investigate the effects of using iPad tablets to display video self‐modeling and activity photos for three preschoolers during circle time. During baseline, all three children demonstrated low levels of engagement and high levels of off‐task behavior compared to peers. The intervention phase consisted of alternating between showing the child the self‐video and photos prior to circle time. A child preference phase was conducted whereby each child self‐selected the video or photo prior to circle time. For all three children both videos and photos led to increased engagement and decreased off‐task behaviors. During the child preference phase, all three children selected the video most frequently. Social validity data demonstrated teacher and child preference for the video self‐modeling condition.  相似文献   

运用任务教学法提高大学英语写作水平     

宛鹏云 《忻州师范学院学报》2007,23(4):122-124

在我国大学英语写作教学仍然存在很多问题,新的写作教学方法有待于进一步研究。文章运用定量和定性分析对任务教学法的应用进行研究,提出了任务教学法在大学英语写作教学中的具体运用模式及其优势。  相似文献