When are workload and workplace learning opportunities related in a curvilinear manner? The moderating role of autonomy

Building on theoretical frameworks like the Job Demands Control model and Action Theory we tested whether the relationship between workload and employees’ experiences of opportunities for workplace learning is of an inverted u-shaped nature and whether autonomy moderates this relationship. We predicted that – at moderate levels of autonomy - workload was positively associated with learning opportunities at low levels of workload, but negatively at high levels of workload. Also, we predicted that low autonomy prevents positive effects of moderate workload from materializing whereas high autonomy makes high workload less destructive to the learning process. Furthermore, we examined whether learning opportunities increase particularly as a function of higher matched levels of workload and autonomy and whether mismatch between workload and autonomy is particularly detrimental to the learning process. We found support for these ideas in two large and heterogeneous samples of working adults using moderated and polynomial regression analysis and subsequent response surface methodology. These results integrate conflicting prior findings and extend Karasek's (1979) active learning hypothesis. They also have clear implications for job redesign practices aiming to promote workplace learning opportunities. For this study, the researchers made use of SERV-data from the Flemish Workability Monitor. Only the authors are responsible for the content of this article

Wanneer bevordert en wanneer hindert werkdruk het werkplek leren?

Building on theoretical frameworks like the Job Demands Control model we tested whether the relationship between workload and employees’ experiences of opportunities for workplace learning is of an inverted u-shaped nature. Furthermore we researched whether autonomy moderates this relationship. We predicted that at moderate levels of autonomy rising workload was associated with increasing learning opportunities at low levels of workload, but with decreasing learning opportunities at high levels of workload. Also, we predicted that low autonomy prevents positive effects of moderate workload from materializing whereas high autonomy makes high workload less destructive to the learning process. We found support for these ideas in a large and heterogeneous sample of Flemish working adults (FWM, 2010). These results integrate conflicting prior findings and extend Karasek’s (1979) active learning hypothesis. They also have clear implications for job redesign practices aiming to promote workplace learning opportunities

In self-defense: reappraisal buffers the negative impact of low procedural fairness on performance

Contrary to an often-found result in the organizational justice literature, we suggest that there may be circumstances under which organization members will not perform poorly in response to being on the receiving end of low procedural fairness. To explain the theoretical mechanism, we integrate the group engagement model of justice with the emotion regulation perspective. Specifically, we argue that the detrimental effect of lower procedural fairness on performance is attenuated when individuals engage in reappraisal. Moreover, this is the case because reappraisal makes lower procedural fairness less likely to undermine self-perceived standing in the organization. Three experiments and a multisource survey among employees reveal support for these predictions. This research contributes to the organizational justice literature by showing that reappraisal can help maintain performance when people have experienced low procedural fairness, extending the typical finding that low procedural fairness undermines performance. Theoretical and practical implications, limitations, and suggestions for future research are discussed

Carbon nanotube thermal interfaces and related applications

The development of thermal interface materials (TIMs) is necessitated by the temperature drop across interfacing materials arising from macro and microscopic irregularities of their surfaces that constricts heat through small contact regions as well as mismatches in their thermal properties. Similar to other types of TIMs, CNT TIMs alleviate the thermal resistance across the interface by thermally bridging two materials together with cylindrical, high-aspect ratio, and nominally vertical conducting elements. Within the community of TIM engineers, the vision driving the development of CNT TIMs was born from measurements that revealed impressively high thermal conductivities of individual CNTs. This vision was then projected to efforts focused on packing many individual CNTs on a single substrate that efficiently conduct heat in parallel and ultimately through many contact regions at CNT-to-substrate contacts. This thesis encompasses a comprehensive investigation of the viability of carbon nanotube based thermal interface materials (CNT TIMs) to efficiently conduct heat across two contacting materials. The efforts in this work were initially devoted to engaging CNT TIMs with an opposing substrate using two bonding techniques. Using palladium hexadecanethiolate, Pd(SC16H35)2 the CNT ends were bonded to an opposing substrate (one-sided interface) or opposing CNT array (two-sided interface) to enhance contact conductance while maintaining a compliant joint. The palladium weld is particularly attractive for its mechanical stability at high temperatures. The engagement of CNT TIMs with an opposing substrate was also achieved by inserting a solder foil between the CNT TIM and opposing substrate and subsequently raising the temperature of the interface above the eutectic point of the solder foil. This bonding technique creates a strong weld that not only reduces the thermal resistance significantly but also minimizes the change in thermal resistance with an applied compressive load. The thermal performance was further improved by infiltrating the CNT TIM with paraffin wax, which serves as an alternate pathway for heat conduction across the interface that ultimately reduces the bulk thermal resistance of the CNT TIM. For CNT TIMs synthesized at the Birck Nanotechnology Center at Purdue University, the thermal resistance was shown to scale linearly with their aggregate, as-grown height. Thus, the bulk thermal resistance can alternatively be tuned by adjusting the as-grown height. The linear relationship between thermal resistance and CNT TIM height provides a simple and efficient methodology to estimate the contact resistance and effective thermal conductivity of CNT TIMs. In this work, the contact resistance and effective thermal conductivity were estimated using two measurement techniques: (i) one-dimensional, steady-state reference bar and (ii) photoacoustic technique. A discrepancy in the estimated contact resistance exists between the two measurement techniques, which is due to the difficulty in measuring the true contact area. In contrast, the effective thermal conductivities estimated from both measurement techniques moderately agreed and were estimated to be on the order of O(1 W/mK). The final chapter is in collaboration with Sandia National Laboratories and focuses on the development of an apparatus to measure the thermal conductivity of insulation materials critical for the operation of molten salt batteries. Molten salt batteries are particularly useful power sources for radar and guidance systems in military applications such as guided missiles, ordinance, and other weapons. Molten salt batteries are activated by raising the temperature of the electrolyte above its melting temperature using pyrotechnic heat pellets. The battery will remain active as long as the electrolyte is molten. As a result, the thermal processes within the components and interactions between them are critical to the overall performance of molten salt batteries. A molten salt battery is typically thermally insulated using wrappable and board-like insulation materials such as Fiberfrax wrap, Fiberfrax board, and Min-K insulation. The Fiberfrax board and Min-K insulation are composites of alumino-silicate and fumed silica-titania, respectively. In Chapter 9, the thermal conductivities of the Fiberfrax board and Min-K insulation were measured under different uniaxial compressive states and ambient environments. The thermal conductivity of the mixed separator pellets (LiCl/MgO/KCl) was also measured along with its contact resistances with interfacing members. To measure the thermal quantities, a steady-state reference bar with thermocouples was employed. The resulting values serve as inputs to a thermal model that aims to predict lifetimes of the batteries. (Abstract shortened by ProQuest.

Zingeving en spiritualiteit in de ouderenzorg

Ouderen in verzorgings- en verpleeghuizen worstelen vaak met ingrijpende zingevingsvragen. Vanuit zorginstellingen is hier helaas weinig aandacht voor. Zorgverleners missen een antenne om zingevingsgerelateerde vragen te herkennen en hier adequaat op in te spelen. Ook zijn zij nauwelijks bekend met de steun die veel ouderen putten uit spiritualiteit en religie. De vraag die ik in mijn scriptie probeer te beantwoorden is welke betekenis zingeving en spiritualiteit hebben in het leven van zorgbehoeftige ouderen, en hoe beide een plek kunnen krijgen binnen de zorg. In het eerste deel van mijn scriptie onderzoek ik wat er onder de begrippen zingeving en spiritualiteit kan worden verstaan. Vervolgens ga ik in op de specifieke zingevingsvragen waar ouderen in zorginstellingen mee worstelen. In deel twee ga ik in op de situatie in de zorg. Welke ontwikkelingen bieden aanknopingspunten om zingeving en spiritualiteit een plek te geven binnen de zorg en waar zitten knelpunten? Aan de hand van de boeken van de Amerikaanse professor Harold Koenig, die veel schreef over religie en spiritualiteit in de zorg, ga ik in op het concept van “spiritual care”: verzorgenden en verpleegkundigen die spirituele zorg bieden aan bewoners van zorginstellingen. Ook besteed ik aandacht aan de rol die (humanistisch) geestelijk verzorgers kunnen spelen bij het integreren van zingeving en spiritualiteit in de zorg

Learning to suspend implicated contrast:The acquisition of <em>ook</em> in Dutch

Children acquire the meaning of ook ‘also’ in Dutch relatively late ( Bergsma 2006 ), although this focus particle is highly frequent. We argue that this late acquisition is caused by a pragmatic rule: contrastive implicature. We follow Sæbø (2004) , who argues that additives are used because without them, the sentences they appear in would be interpreted as contrastive in relation to the context. Data from a sentence completion task administered to Dutch L1 learners (N = 62, ages 4;0–5;11) show that, on average, four-year-olds do not distinguish sentences with ook from sentences without ook. Five-year-olds do better on sentences with ook but worse on sentences without it. We argue that they have generally acquired contrastive implicature: they apply the correct contrastive interpretation to sentences without ook, but overgeneralize this implicature to sentences with ook, before completely acquiring the meaning of ook

Does the Normalized Difference Vegetation Index explain spatial and temporal variability in sap velocity in temperate forest ecosystems?

Understanding the link between vegetation characteristics and tree transpiration is a critical need to facilitate satellite-based transpiration estimation. Many studies use the Normalized Difference Vegetation Index (NDVI), a proxy for tree biophysical characteristics, to estimate evapotranspiration. In this study, we investigated the link between sap velocity and 30&thinsp;m resolution Landsat-derived NDVI for 20 days during 2 contrasting precipitation years in a temperate deciduous forest catchment. Sap velocity was measured in the Attert catchment in Luxembourg in 25 plots of 20×20&thinsp;m covering three geologies with sensors installed in two to four trees per plot. The results show that, spatially, sap velocity and NDVI were significantly positively correlated in April, i.e. NDVI successfully captured the pattern of sap velocity during the phase of green-up. After green-up, a significant negative correlation was found during half of the studied days. During a dry period, sap velocity was uncorrelated with NDVI but influenced by geology and aspect. In summary, in our study area, the correlation between sap velocity and NDVI was not constant, but varied with phenology and water availability. The same behaviour was found for the Enhanced Vegetation Index (EVI). This suggests that methods using NDVI or EVI to predict small-scale variability in (evapo)transpiration should be carefully applied, and that NDVI and EVI cannot be used to scale sap velocity to stand-level transpiration in temperate forest ecosystems.</p