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排序方式: 共有690条查询结果,搜索用时 15 毫秒
1.
Vili Lehdonvirta 《New Technology, Work and Employment》2018,33(1):13-29
Gig economy platforms seem to provide extreme temporal flexibility to workers, giving them full control over how to spend each hour and minute of the day. What constraints do workers face when attempting to exercise this flexibility? We use 30 worker interviews and other data to compare three online piecework platforms with different histories and worker demographics: Mechanical Turk, MobileWorks, and CloudFactory. We find that structural constraints (availability of work and degree of worker dependence on the work) as well as cultural‐cognitive constraints (procrastination and presenteeism) limit worker control over scheduling in practice. The severity of these constraints varies significantly between platforms, the formally freest platform presenting the greatest structural and cultural‐cognitive constraints. We also find that workers have developed informal practices, tools, and communities to address these constraints. We conclude that focusing on outcomes rather than on worker control is a more fruitful way to assess flexible working arrangements. 相似文献
2.
针对无线传感器网络分簇算法中能量分布不均衡导致的"热区"和簇头负载过重问题,提出了一种基于PSO算法优化簇头选举的非均匀分簇算法。在候选簇头选举和竞争半径计算过程中综合考虑节点动态能量、节点密度和节点距基站距离,将网络进行非均匀分簇,并引入PSO算法进行最终簇头选举。根据节点能量、节点密度和距基站距离确定簇间单跳多跳结合的路由规则,选取代价函数小的节点作为下一跳节点。基于节点信息熵确定融合阈值,进行簇内数据融合剔除冗余数据。仿真结果表明,改进算法的数据传输量比EEUC算法和UCRA算法分别提高了20%和10%,提升了数据的融合效率,有效延长了网络生命周期,簇头能量消耗得到均衡,减少了网络能量消耗,网络的整体性能显著优于其他对比算法。 相似文献
3.
Mohammad Karim Sohrabi 《Enterprise Information Systems》2018,12(6):674-694
The computational complexity, huge memory space requirement, and time-consuming nature of frequent pattern mining process are the most important motivations for distribution and parallelization of this mining process. On the other hand, the emergence of distributed computational and operational environments, which causes the production and maintenance of data on different distributed data sources, makes the parallelization and distribution of the knowledge discovery process inevitable. In this paper, a gossip based distributed itemset mining (GDIM) algorithm is proposed to extract frequent itemsets, which are special types of frequent patterns, in a wireless sensor network environment. In this algorithm, local frequent itemsets of each sensor are extracted using a bit-wise horizontal approach (LHPM) from the nodes which are clustered using a leach-based protocol. Heads of clusters exploit a gossip based protocol in order to communicate each other to find the patterns which their global support is equal to or more than the specified support threshold. Experimental results show that the proposed algorithm outperforms the best existing gossip based algorithm in term of execution time. 相似文献
4.
This study details how psychological, financial, and social factors shape employee deviant interpersonal behaviors during a pandemic. Data were collected with a survey of 372 front-line employees of hotels and analyzed with PLS-SEM. The findings showed social disconnectedness and perceived risk of unemployment leads to perceived isolation, which further creates depression in employees. The findings also showed that depression is positively related to employee deviance. Financial strain is a major cause of perceived isolation, depression, and deviant behaviors among front-line employees. Results also proved that social support reduces fear of isolation, depression, and employee deviance. This study provides guidelines that hotels need to understand the psychological stance of employees and design policies to overcome employee perceived fears and psychological disorders. 相似文献
5.
Eva-Ellen Weiß 《International Journal of Human Resource Management》2020,31(5):682-704
AbstractPerceived work-related stress has increased notably in recent years, reducing individuals’ well-being and increasing organizations’ and economies’ costs. This study focuses on worktime control as a key approach to reducing work stress, as the extant research on its effects reports inconsistent results. The study argues that comparisons play a major role in how work stress, conceptualized as effort-reward imbalance, occurs. Ordinary least squares is used to test hypotheses with a sample of 1721 employees from Germany to determine whether employees’ prior worktime control and employees’ referents’ worktime control affect the relationship between worktime control and work stress. Results show that (1) worktime control is negatively associated with the experience of work stress, (2) employees’ prior worktime control moderates the relationship between worktime control and work stress, and (3) there is no moderating effect of employees’ referents’ worktime control. The results are discussed in light of gift-exchange theory and related empirical findings. 相似文献
6.
针对认知无线传感器网络中频谱接入算法的频谱利用率不高、重要经验利用率不足、收敛速度慢等问题,提出了一种采用优先经验回放双深度Q-Learning的动态频谱接入算法。该算法的次用户对经验库进行抽样时,采用基于优先级抽样的方式,以打破样本相关性并充分利用重要的经验样本,并采用一种非排序批量删除方式删除经验库的无用经验样本,以降低能量开销。仿真结果表明,该算法与采用双深度Q-Learning的频谱接入算法相比提高了收敛速度;与传统随机频谱接入算法相比,其阻塞概率降低了6%~10%,吞吐量提高了18%~20%,提高了系统的性能。 相似文献
7.
本研究设计了一种结合二氧化碳传感器、PM2.5粉尘传感器、TVOC传感器来实现智能更新长途客车封闭空间内污浊空气的长途客车车载新风系统。本系统由各项传感器实时采集车厢内CO2、PM2.5、TVOC等数据上传至单片机,单片机判断各项数据是否超过设定阈值,若超过设定阈值,新风系统自动工作改变进、排风量;反之,新风系统不工作,实现智能控制。实验证明,本系统具有明显地改善长途客车内空气质量的效果,能够更好地保护人体健康。 相似文献
8.
In this article, we develop, and empirically test, a moderated mediation model of the effects of flexible leave on employees' organizational attachment. Drawing on a social exchange framework and signaling theory, we explore how the material and non-material nature of exchange between the employer and employee shapes their relationship. First, we show that the relationship between the availability of flexible leave and organizational attachment is shaped by two competing mediators, perceived organizational support (POS) and perceived flexibility stigma. Second, we delineate between availability and use of the policy, to show how the effect of POS is enhanced and perceived flexibility stigma reduced, with use. Our findings demonstrate that the relationship between the availability of flexible leave and organizational attachment is complex, but is enhanced through use of flexible leave. We contribute toward HRM scholarship about the relationship between employees' experience of HR practices and their corresponding impact on employees' subsequent behavior. 相似文献
9.
为了研究网架结构的损伤检测方法,根据应变能密度理论,提出采用单元模态应变能密度差值作为网架结构损伤识别指标的方法,以损伤单元模态应变能密度差值的大小初步确定单元的损伤程度。分析了5种具有代表性的损伤工况,并在数值计算结果中引入了白噪声。结果显示,在一阶模态下,针对单损伤、多损伤和轻微损伤、严重损伤等不同损伤工况,损伤杆件的模态应变能密度差值均为高值。因此,该方法可以有效识别出网架结构的损伤位置,根据损伤单元的模态应变能密度差值大小初步确定单元的损伤程度,且在一定的噪声水平下具有较强的鲁棒性,对网架结构损伤识别具有参考价值。 相似文献
10.
为了避免倒车过程中因视觉盲区可能出现的安全隐患问题[1][2],文章采用飞思卡尔单片机做主机,Aptina图像传感器ASX340[3]做从机,利用ASX340内部的OVERLAY位图叠加系统,设计了一种能够将倒车过程中实时的车辆尾部的影像,距离障碍物的安全距离,倒车轨迹路径等信息提供驾驶员倒车影像系统[9][10]。使用HYRes3_1、Imatest软件[4]测量了影像图像质量的主要因素。测量结果表明成像质量能够满足目前车厂的要求。 相似文献