Plant photosynthesis and biomass production are associated with the amount of intercepted light, especially the light distribution inside the canopy. Three virtual canopies (n = 80, 3.25 plants/m2) were constructed based on average leaf size of the digitized plant structures: ‘small leaf’ (98.1 cm2), ‘medium leaf’ (163.0 cm2) and ‘big leaf’ (241.6 cm2). The ratios of diffuse light were set in three gradients (27.8%, 48.7%, 89.6%). The simulations of light interception were conducted under different ratios of diffuse light, before and after the normalization of incident radiation. With 226.1% more diffuse light, the result of light interception could increase by 34.4%. However, the 56.8% of reduced radiation caused by the increased proportion of diffuse light inhibited the advantage of diffuse light in terms of a 26.8% reduction in light interception. The big-leaf canopy had more mutual shading effects, but its larger leaf area intercepted 56.2% more light than the small-leaf canopy under the same light conditions. The small-leaf canopy showed higher efficiency in light penetration and higher light interception per unit of leaf area. The study implied the 3D structural model, an effective tool for quantitative analysis of the interaction between light and plant canopy structure.
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Studies among people with dementia demonstrated that the sleep quality and rhythm improves significantly when people are exposed to ambient bright light. Since almost half of the healthy older people also indicate to suffer from chronic sleep disorders, the question arises whether ambient bright light can be beneficial to healthy older people. Particularly the effect on sleep/wake rhythm in relation to the exposure to natural light is the focus. It was hypothesised that the sleep quality would be worse in winter due to a lower daylight dose than in summer due to the lower illuminance and exposure duration. A field study was conducted to examine the relationship between daylight exposure and sleep quality in 14 healthy older adults living independently in their own dwellings in the Netherlands. All participants were asked to take part of the study both during the summer period as well as during the winter period. Therefore, they had to wear an actigraph for five consecutive days which measured sleep, activity and light exposure. Results confirmed that people were significantly longer exposed to high illumination levels (>1000 lx) in summer than in winter. Sleep quality measures, however, did not differ significantly between summer and winter. A significant, positive correlation was found between exposure duration to high illuminance from daylight during the day and the sleep efficiency the following night in summer, implying that being exposed to high illuminance for a longer time period has a positive effect on sleep efficiency for the individual data. There was also a tendency of less frequent napping in case of longer exposure duration to light for both seasons. Sleep quality does not differ between summer and winter but is related to the duration of the exposure to bright light the day prior to the night. CC-BY Original article at http://solarlits.com/jd/5-14 http://dx.doi.org/10.15627/jd.2018.2 https://www.dehaagsehogeschool.nl/onderzoek/lectoraten/details/urban-ageing#over-het-lectoraat
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Purpose: The purpose of this paper is to report the grounded theory empirical validation on key categories within a design-led methodology to envision urban futures. The paper focuses on the editorial products and the design concepts that constitute the heart of the approach. An original elaboration of trend clusters is presented as an exemplification of the outcome of this trend research approach. Although the approach was not created from the viewpoint of tourism and leisure, bibliographic notes on place-making complement it for this journal. Design/methodology/approach: The paper presents empirical findings extracted by the means of the grounded theory, with the purpose to empirically validate two key categories (product and process) of a urban futures methodology. The methodology is an application of High Design, the process in use at Royal Philips BV for two decades. This methodology is contextualized within the constructivist episteme, as defined by the editors of this journal in a separate publication. Bibliographic references to place-making complete the paper. Findings: The following findings are provided: empirical validation of the city.people.light communication platform (qualitative research); empirical validation of the city.people.light workshop practice (qualitative research); and bibliographic descriptions of the design process governing city.people.light and newly developed urban futures trend clusters, at European level, as an exemplification of the program/approach outcome. Research limitations/implications: The paper is structured according to a multi-layered editorial focus. Empirical findings were generated at primary research level in a 2013-2015 grounded theory projected by the author. Furthermore, the author directed the research processes and products that are the object of empirical validation. Newly defined elaborations and a discussion thereof is offered, taking into account contemporary place-making issues. Practical implications: The original design-based methodology is a structured practice in urban futures from applied sciences and corporate innovation viewpoint. In this paper, its key categories are empirically validated through the grounded theory. Additionally, outcome from the original foresight programs is presented and a bibliographic review is provided from the viewpoint of place-making. Social implications: The co-creative methodology herein empirically validated is socio-cultural centered, with a strong drive to coutnerbalance the positivist and engineering corporate mindset through a humanistic concern for people. The framework in terms of place-making takes into account postmodern evolutions of the field. Originality/value: The paper benefits from a unique mix of: epistemic note on tourism, leisure, and the future; original urban futures scenarios and design concepts from a world class corporate innovation program; and the actual empirical core of the grounded theory validation as performed in a dedicated research project. These three separate streams are mutually related.
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The EU Climate and Energy Policy Framework targets a 40% reduction in Greenhouse Gases (GHGs) emission by companies (when compared to 1990’s values) in 2030 [1]. Preparing for that future, many companies are working to reach climate neutrality in 2030. For water and wastewater treatment plants aeration processes could represent up to 70% of the whole energy consumption of the plant. Thus, a process which must be carefully evaluated if climate neutrality is a target. VortOx is an alternative to reduce power consumption in aeration processes. It is structured to test the applicability of geometrically constrained vortices in a hyperbolic funnel (aka “Schauberger”- funnel) as an innovative aeration technique for this industry. Recent investigations have shown that such systems allow an average of 12x more oxygen transfer coefficients (KLa) than that of comparable methods like air jets or impellers [10]. However, the system has a relatively small hydraulic retention time (HRT), which compromises its standard oxygen transfer ratio (SOTR). Additionally, so far, the system has only been tested in pilot (lab) scale. Vortox will tackle both challenges. Firstly, it will test geometry and flow adaptations to increase HRT keeping the same KLa levels. And secondly, all will be done using a real scale hyperbolic funnel and real effluent from Leeuwarden’s wastewater treatment plant demo-site. If proven feasible, Vortox can be a large step towards climate neutral water and wastewater treatment systems.
