Semi-Automatic Generation of Assembly Instructions for Open Source Hardware

Documentation is an essential component of Open Source Hardware (OSH) projects both for co-development and replication of designs. However, creating documentation and keeping it up-to-date is often challenging and time-intensive. There are several systems that focus on this documentation challenge but they are limited in their support for keeping documentation up-to-date and relating CAD designs to documentation. This article proposes a semi-automated solution that relates the CAD design semantically to a textual specification from which we generate assembly instructions semi-automatically. Our system contains a CAD plugin and a compiler for the textual specification with which we show that we can replicate a state-of-the-art assembly manual to a high degree, that we can automate significant parts of the documentation process, and that our system can effectively adapt to documentation changes as a result of evolving designs. Our system leads to a methodology that we name “CAD-coupled documentation” integrating CAD design with the documentation process

Long-term growth and yield responses of olive trees to different irrigation regimes

The aim of this work was to evaluate long-term effects of different irrigation regimes on mature olive trees growing under field conditions. A 9-year experiment was carried out. Three irrigation treatments were applied: no irrigation, water application considering soil water content (short irrigation), or irrigation without considering soil water reserves and applying a 20% of extra water as a leaching fraction (long irrigation). Leaf water content, leaf area, vegetative growth, yield and fruit characteristics (fruit size, pulp:stone ratio and oil content) were determined yearly. Results showed that growth parameters did not show significant differences as a consequence of applied water. Yield was increased in irrigated trees compared to non-irrigated ones, but little differences between short and long irrigation were observed, only when accumulated yield from 1998 to 2006 was considered. Irrigation did not cause significant differences in fruit size or pulp:stone ratio either. Irrigation regimes similar to those applied in this experiment, under environmental conditions with relatively high mean annual precipitation, does not increase growth, yield or fruit characteristics when compared to rain-fed treatment, and consequently, the installation of a irrigation system could be not financially profitable.

Renewable Energy for Smallholder Irrigation: A Technology Adoption Toolkit

Smallholders are the backbone of livelihoods in the Global South. Yet, many remain water- and energy-insecure. For this challenge, this study presents a toolkit to stimulate the sustained adoption of renewable energy-powered water pumps for smallholder irrigation. A human-centered design method was used to co-create it. It first consisted of a prototype that was tested by experts. Their feedback was crucial to further improving the toolkit, thereby making it a more robust instrument. The design posed limitations worth considering in future research. Additionally, the spread of water pumps implies environmental and economic concerns. To enhance its benefits, the toolkit still requires thorough testing in diverse contexts.Water Resource

Antioxidant defences and oxidative damage in salt-treated olive plants under contrasting sunlight irradiance

The interactive effects of root-zone salinity and sunlight on leaf biochemistry, with special emphasis on antioxidant defences, were analysed in Olea europaea L. cv. Allora, during the summer period. Plants were grown outside under 15% (shade plants) or 100% sunlight (sun plants) and supplied with 0 or 125 mM NaCl. The following measurements were performed: (1) the contribution of ions and soluble carbohydrates to osmotic potentials; (2) the photosystem II (PSII) photochemistry and the photosynthetic pigment concentration; (3) the concentration and the tissue-specific distribution of leaf flavonoids; (4) the activity of antioxidant enzymes; and (5) the leaf oxidative damage. The concentrations of Na + and Cl - were significantly greater in sun than in shade leaves, as also observed for the concentration of the 'antioxidant' sugaralcohol mannitol. The de-epoxidation state of violaxanthin-cycle pigments increased in response to salinity stress in sun leaves. This finding agrees with a greater maximal PSII photochemistry (F v/F m) at midday, detected in salt-treated than in control plants, growing in full sunshine. By contrast, salt-treated plants in the shade suffered from midday depression in F v/F m to a greater degree than that observed in control plants. The high concentration of violaxanthin-cycle pigments in sun leaves suggests that zeaxanthin may protect the chloroplast from photo-oxidative damage, rather than dissipating excess excitation energy via non-photochemical quenching mechanisms. Dihydroxy B-ring-substituted flavonoid glycosides accumulate greatly in the mesophyll, not only in the epidermal cells, in response to high sunlight. The activity of antioxidant enzymes varied little because of sunlight irradiance, but declined sharply in response to high salinity in shade leaves. Interestingly, control and particularly salt-treated plants in the shade underwent greater oxidative damage than their sunny counterparts. These findings, which conform to the evolution of O. europaea in sunny environments, suggest that under partial shading, the antioxidant defence system may be ineffective to counter salt-induced oxidative damage

Long term responses of olive trees to salinity

Water demand for irrigation is increasing in olive orchards due to enhanced yields and profits. Because olive trees are considered moderately tolerant to salinity, irrigation water with salt concentrations that can be harmful for many of fruit tree crops is often used without considering the possible negative effects on olive tree growth and yield. We studied salt effects in mature olive trees in a long term field experiment (1998-2006). Eighteen-year-old olive trees (Olea europaea L.) cv. Picual were cultivated under drip irrigation with saline water composed of a mixture of NaCl and CaCl2. Three irrigation regimes (i. no irrigation; ii. water application considering soil water reserves, short irrigation; iii. water application without considering soil water reserves and adding a 20% more as a leaching fraction, long irrigation) and three salt concentrations (0.5, 5 or 10dSm-1) were applied. Treatments were the result of the combination of three salt concentrations with two irrigation regimes, plus the non-irrigated treatment. Growth parameters, leaf and fruit nutrition, yield, oil content and fruit characteristics were annually studied. Annual leaf nutrient analyses indicate that all nutrients were within the adequate levels. After 8 years of treatment, salinity did not affect any growth measurement and leaf Na+ and Cl- concentration were always below the toxicity threshold of 0.2 and 0.5%, respectively. Annual and accumulated yield, fruit size and pulp:stone ratio were also not affected by salts. However, oil content increased linearly with salinity, in most of the years studied. Soil salinity measurements showed that there was no accumulation of salts in the upper 30cm of the soil (where most of the roots are present) because of leaching by rainfall at the end of the irrigation period. Results suggest that a proper management of saline water, supplying Ca2+ to the irrigation water, using drip irrigation until winter rest and seasonal rainfall typical of the Mediterranean climate leach the salts from the first 0-60cm depth, and growing a tolerant cultivar, can allow using high saline irrigation water (up to 10dSm-1) for a long time without affecting growth and yield in olive trees.Olea europaea Salt tolerance Drip fertigation Calcium supply