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排序方式: 共有146条查询结果,搜索用时 15 毫秒
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Daniel Biedermann Jan Schneider Hendrik Drachsler 《Journal of Computer Assisted Learning》2021,37(5):1217-1231
Digital distractions can interfere with goal attainment and lead to undesirable habits that are hard to get red rid of. Various digital self-control interventions promise support to alleviate the negative impact of digital distractions. These interventions use different approaches, such as the blocking of apps and websites, goal setting, or visualizations of device usage statistics. While many apps and browser extensions make use of these features, little is known about their effectiveness. This systematic review synthesizes the current research to provide insights into the effectiveness of the different kinds of interventions. From a search of the ‘ACM’, ‘Springer Link’, ‘Web of Science’, ’IEEE Xplore’ and ‘Pubmed’ databases, we identified 28 digital self-control interventions. We categorized these interventions according to their features and their outcomes. The interventions showed varying degrees of effectiveness, and especially interventions that relied purely on increasing the participants' awareness were barely effective. For those interventions that sanctioned the use of distractions, the current literature indicates that the sanctions have to be sufficiently difficult to overcome, as they will otherwise be quickly dismissed. The overall confidence in the results is low, with small sample sizes, short study duration, and unclear study contexts. From these insights, we highlight research gaps and close with suggestions for future research. 相似文献
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Self-control is demonstrated when a less desirable immediate outcome is chosen to ensure a substantially better future. In a novel animal analogue of this situation, primary reinforcement was delivered in both the initial and terminal links of a concurrent chain schedule. Rats made initial link choices between equal amounts of ethanol-free or ethanol-containing milk. Choosing the ethanol-free reinforcer resulted in delivery of the larger terminal link reinforcer and was thus analogous to self-control. Self-control decreased as the delay between initial and terminal links increased. The results have implications for human choice situations where decisions are made between two immediately available reinforcement alternatives each associated with a different delayed outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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六边形磁链轨迹的无刷直流电机直接自控制 总被引:2,自引:4,他引:2
按照定子磁链运动轨迹的不同,直接转矩可分为2大流派,圆形轨迹称为直接转矩控制,六边形轨迹称为直接自控制。近来国外尝试将直接转矩控制应用到无刷直流电机上,但受关断相电压不确定的影响,定子磁链与给定磁链均呈现周期性变化,在一个周期内其幅值逐渐增大,计算复杂。为此,该文将基本直接自控制引入无刷直流电机,将定子磁链的3个投影与1个常数比较,以更简单的结构实现了无刷直流电机地高性能控制。仿真与实验证明:常见的无刷直流电机三三导通方式可以看作是直接自控制的特例,对应直接自控制在全速运行;转矩动态响应时间不超过1ms。 相似文献
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将变结构滑模控制的原理引入到无速度传感器直接转矩控制系统中,以改善系统的动态及稳态性能,并用仿真验证了所设计的方案的有效性。 相似文献
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Objective: Individuals may desire to diet or restrain from eating certain foods while attempting to quit smoking out of concern for weight gain. However, previous research and clinical tobacco treatment guidelines suggest that concurrent dieting may undermine attempts to quit smoking. The current study applied the self-control strength model, which posits that self-regulation relies on a limited strength that is consumed with use, to test whether resisting tempting sweets would lead to a greater likelihood of subsequent smoking. Design: Participants were 101 cigarette smokers randomly assigned to resist eating either from a tempting plate of sweets or from a plate of less tempting vegetables. All participants were then given a 10-min recess. Main Outcome Measures: Whether participants smoked during the break, measured with a breath carbon monoxide sample, served as the primary dependent variable. Results: As predicted, participants who resisted sweets were more likely to smoke during the break (53.2%) than those who resisted vegetables (34.0%), χ2(1, N = 101) = 3.65 p 相似文献
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Berkman Elliot T.; Dickenson Janna; Falk Emily B.; Lieberman Matthew D. 《Canadian Metallurgical Quarterly》2011,30(2):186
Objective: Understanding the psychological processes that contribute to smoking reduction will yield population health benefits. Negative mood may moderate smoking lapse during cessation, but this relationship has been difficult to measure in ongoing daily experience. We used a novel form of ecological momentary assessment to test a self-control model of negative mood and craving leading to smoking lapse. Design: We validated short message service (SMS) text as a user-friendly and low-cost option for ecologically measuring real-time health behaviors. We sent text messages to cigarette smokers attempting to quit eight times daily for the first 21 days of cessation (N-obs = 3,811). Main outcome measures: Approximately every two hours, we assessed cigarette count, mood, and cravings, and examined between- and within-day patterns and time-lagged relationships among these variables. Exhaled carbon monoxide was assessed pre- and posttreatment. Results: Negative mood and craving predicted smoking two hours later, but craving mediated the mood–smoking relationship. Also, this mediation relationship predicted smoking over the next two, but not four, hours. Conclusion: Results clarify conflicting previous findings on the relation between affect and smoking, validate a new low-cost and user-friendly method for collecting fine-grained health behavior assessments, and emphasize the importance of rapid, real-time measurement of smoking moderators. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Recent research has suggested that practicing small acts of self-control can lead to an improvement in self-control performance. Because smoking cessation requires self-control, it was hypothesized that a treatment that builds self-control should help in quitting smoking. A total of 122 smokers either practiced small acts of self-control for 2 weeks before quitting smoking or practiced a task that increased their awareness of self-control or feelings of confidence, without exercising self-control. Their smoking status was assessed using daily telephone calls and biochemically verified. Individuals who practiced self-control remained abstinent longer than those who practiced tasks that did not require self-control. Supplemental analyses suggested that the increased survival times were a product of building self-control strength and were not produced by changes in feelings that practicing should help in cessation, effort exerted on the practice task, or thinking more about self-control while practicing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
传统的电缆绕包工序生产过程中,带材的绕包张力变化较大(2.78倍),影响电缆产品质量.本文介绍一种自反馈式恒张力放带装置,使整盘带材在连续绕包过程中,其放带张力的变化仅有±5%,有效的提高了带材绕包的工序质量;分析了该装置的结构及设计的步骤和方法,并为该装置的运动分析提供了一定的理论依据. 相似文献