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Digital labour platforms have become increasingly common for the trade of a range of digitally transferable services. To help participants mitigate the uncertainty that is inherent to trading on digital platforms, feedback mechanisms have become the main tool to gauge the ‘performed’ quality and reliability of platform participants. Based on an analysis of 750 written feedback texts, this article first examines which freelancer qualities (technical skills, generic skills or personal competences) matter most to clients and, therefore, are instrumental to the building of a freelancer’s digital reputation on a platform and, second, how exactly these feedback texts help reduce uncertainty when trading via a platform. Herewith, this paper adds to a deeper understanding of the ‘rules of the game’ on digital labour platforms.

The use of integrated heaters is widespread in silicon photonics for waveguide temperature control. The dynamical behavior of the heaters is important for determining their usefulness for certain applications. There exists ambiguity in the literature when it comes to reporting the thermo-optic time constants of Si photonic devices. Many studies report devices with different heating and cooling times without providing an explanation to this phenomenon. In this paper, a comprehensive theoretical framework is developed for interpreting experimental results. This framework is developed for interferometric devices (Mach–Zehnder-based) and resonant devices (rings). With this framework, the impact of measurement conditions on the obtained thermo-optic time constant can be simulated, and we provide an explanation to the observed difference between heating and cooling time constants. We also provide guidelines on how to disentangle optical non-linearities from the pure thermal response, which should be useful in for future reporting of thermo-optic time constants.

With ever increasing integration density of electronic components, the demand for cooling solutions capable of removing the heat generated by such systems grows along with it. It has been shown that a viable answer to this demand is the use of direct liquid jet impingement. While this method can generally be scaled to the cooling of large areas, this is restricted by the necessity of coolant flow rate scaling. In this study, the benefits and restrictions of using increased nozzle pitch to remedy the increasing demand for overall flow rate are investigated. To this end, a model is validated against experimental findings and then used for computational fluid dynamics simulations, exploring effects of the pitch change for micro-scale nozzle diameters and nozzle-to-target spacings. It is found that while this method is efficient in adjusting the tradeoff between total coolant flow rate and pressure drop up to a certain pint, the occurrence of a hydraulic jump in the cavity causes a deterioration of its effect for large nozzle pitches.

The use of integrated heaters is widespread in silicon photonics for waveguide temperature control. The dynamical behavior of the heaters is important for determining their usefulness for certain applications. There exists ambiguity in the literature when it comes to reporting the thermo-optic time constants of Si photonic devices. Many studies report devices with different heating and cooling times without providing an explanation to this phenomenon. In this paper, a comprehensive theoretical framework is developed for interpreting experimental results. This framework is developed for interferometric devices (Mach–Zehnder-based) and resonant devices (rings). With this framework, the impact of measurement conditions on the obtained thermo-optic time constant can be simulated, and we provide an explanation to the observed difference between heating and cooling time constants. We also provide guidelines on how to disentangle optical non-linearities from the pure thermal response, which should be useful in for future reporting of thermo-optic time constants. [ABSTRACT FROM AUTHOR]

WA detailed thermal analysis of a hybrid, flip-chip InP-Si DFB laser is presented in this work. The lasers were experimentally tested at different operating temperatures, which allowed for deriving their thermal performance characteristics: the temperature dependence of threshold current, lasing slope, and output spectrum. Using these data, the laser thermal resistance was calculated (Rth = 75.9 K/W), which allows for predicting the laser temperature during operation. This metric is also used to validate the thermal finite element models of the laser. A sensitivity study of the laser temperature was performed using these models, and multiple routes for minimising both the laser thermal resistance and thermal coupling to the carrier die are presented. The most effective way of decreasing the laser temperature is the direct attachment of a heat sink on the laser top surface.

Bamboo (Phyllostachys sp.) is considered a sustainable resource that can replace fossil fuel‐based products. Its additional ability to sequester organic carbon in the soil (SOC) makes it a promising nature‐based solution for combating climate change. However, bamboo's soil C storage potential may vary considerably between species or growing conditions and needs to be better quantified, especially in temperate climates where data are lacking. In the present research, the SOC dynamics of plots converted from grassland to plantations of three bamboo species (i.e. Phyllostachys nigra, Phyllostachys aurea and Phyllostachys aureosulcata), planted 12 years ago on podzol (World Reference Base classification) in the Belgian Campine region, have been studied. Soil and root samples were taken until a depth of 40 cm using a 10 cm interval. Besides, the total belowground C stability (mgCO2‐C g−1 C h−1) was assessed by measuring during 3 months the carbon dioxide (CO2) efflux relative to the belowground C stock. Based on an equivalent soil mass, only P. aureosulcata, the species with the highest culm basal area, had a significant (p <.001) SOC increase of 5.0 kg C m−2 (relative increase of +94%) as compared with grassland. Considering the sum of C stocks in the soil, roots and leaf litter, all bamboo species showed significant (p <.001) C storage, i.e. +3.6 kg C m−2 (+64%), +5.3 kg C m−2 (+94%) and +8.6 kg C m−2 (+151%) for P. nigra, P. aurea and P. aureosulcata, respectively. In addition, bamboo's relative basal CO2 efflux (0.007, 0.006 and 0.008 mgCO2‐C g−1 C h−1, respectively) was remarkably lower than in the grassland (0.012 mgCO2‐C g−1 C h−1), though it was only significant for P. aurea. This study highlights that converting temperate permanent grassland into Phyllostachys bamboo plantation can result in net and rapid organic C storage by increasing the total belowground C stability and C input. Further research regarding the net CO2 balance of bamboo‐derived products is still required to fully assess its climate change mitigation potential. [ABSTRACT FROM AUTHOR]

Although serious games are more and more used for learning goals, high-quality empirical studies to prove the effectiveness of serious games are relatively scarce. In this paper, three empirical studies are presented that investigate the effectiveness of serious games as opposed to traditional classroom instruction on learning features as well as learning outcomes. All three studies used a similar longitudinal case-control study design and measured the same set of learning features (control, challenge, feedback, engagement and social interaction). Learning outcomes were measured by self-report and knowledge tests. Results of the three studies show that students that played the serious games scored higher on features associated with high-quality learning. Furthermore, the studies show that serious gaming is more effective on self-reported learning outcomes than traditional classroom instruction. Effects of serious gaming on the knowledge tests were not found. The studies serve as a first step to the development of a generic evaluation framework for serious gaming.

With ever increasing integration density of electronic components, the demand for cooling solutions capable of removing the heat generated by such systems grows along with it. It has been shown that a viable answer to this demand is the use of direct liquid jet impingement. While this method can generally be scaled to the cooling of large areas, this is restricted by the necessity of coolant flow rate scaling. In this study, the benefits and restrictions of using increased nozzle pitch to remedy the increasing demand for overall flow rate are investigated. To this end, a model is validated against experimental findings and then used for computational fluid dynamics simulations, exploring effects of the pitch change for micro-scale nozzle diameters and nozzle-to-target spacings. It is found that while this method is efficient in adjusting the tradeoff between total coolant flow rate and pressure drop up to a certain pint, the occurrence of a hydraulic jump in the cavity causes a deterioration of its effect for large nozzle pitches. [ABSTRACT FROM AUTHOR]

Digital labour platforms have become increasingly common for the trade of a range of digitally transferable services. To help participants mitigate the uncertainty that is inherent to trading on digital platforms, feedback mechanisms have become the main tool to gauge the 'performed' quality and reliability of platform participants. Based on an analysis of 750 written feedback texts, this article first examines which freelancer qualities (technical skills, generic skills or personal competences) matter most to clients and, therefore, are instrumental to the building of a freelancer's digital reputation on a platform and, second, how exactly these feedback texts help reduce uncertainty when trading via a platform. Herewith, this paper adds to a deeper understanding of the 'rules of the game' on digital labour platforms. [ABSTRACT FROM AUTHOR]