Occupational exoskeletons hold promise in preventing musculoskeletal disorders, but their effectiveness relies on their long-term use by workers. This study aims to characterize the adoption process of occupational exoskeletons by analyzing the experiences of 25 operators. Using a mixed-methods approach, both quantitative and qualitative data were collected before and during a four-week familiarization period.
View Article and Find Full Text PDFHumans have developed a prolonged and special relationship with their tools, which themselves exhibit the propensity to become ever more intelligent across the years. A 'smart tool' is defined as to representing any entity, machine, or device that can complete an informational, mechanical, or electronic work. This work explains the development of the Smart Tool Proneness Questionnaire (STP-Q), which is designed to measure an individual's propensity to use smart tools.
View Article and Find Full Text PDFOpenMATB is an open-source variant of the Multi-Attribute Task Battery (MATB) and is available under a free software license. MATB consists of a set of tasks representative of those performed in aircraft piloting. It is used, in particular, to study the effect of automation on decision-making, mental workload, and vigilance.
View Article and Find Full Text PDFObjective: We tested Hancock and Szalma's mental workload model, which has never been experimentally validated at a global level with the measure of the pre-ejection period (PEP), an index of beta-adrenergic sympathetic impact.
Background: Operators adapt to mental workload. When mental workload level increases, behavioral and physiological adaptability intensifies to reduce the decline in performance.
A seminal work by Sheridan and Verplank depicted 10 levels of automation, ranging from no automation to an automation that acts completely autonomously without human support. These levels of automation were later complemented with a four-stage model of human information processing. Next, human-machine cooperation centred models and associated cooperation modes were introduced.
View Article and Find Full Text PDFWe examined the effects of time pressure on duration estimation in a verbal estimation task and a production task. In both temporal tasks, participants had to solve mazes in two conditions of time pressure (with or without), and with three different target durations (30 s, 60 s, and 90 s). In each trial of the verbal estimation task, participants had to estimate in conventional time units (minutes and seconds) the amount of time that had elapsed since they started to solve the maze.
View Article and Find Full Text PDFObjective: The objective was to characterize multitask resource reallocation strategies when managing subtasks with various assigned values.
Background: When solving a resource conflict in multitasking, Salvucci and Taatgen predict a globally rational strategy will be followed that favors the most urgent subtask and optimizes global performance. However, Katidioti and Taatgen identified a locally rational strategy that optimizes only a subcomponent of the whole task, leading to detrimental consequences on global performance.
The operating room (OR) is a high-risk complex setting, where patient safety relies on the coordinated efforts of multiple team members. However, little attention has been paid to evaluating the strategies employed by OR practitioners to prevent and correct incidents that inevitably occur during surgery. Therefore, we were prompted to investigate human factor (HF) engineering methods that have been used in an innovative way in order to systematically observe and analyze the management of incidents in the neurosurgical OR of a French university hospital.
View Article and Find Full Text PDFOlive-mill wastes represent a significant environmental problem in Mediterranean areas due to their important production during a short period of time. Their high polyphenol, lipid and organic acid concentrations turn them into phytotoxic wastes. This work examined the evolution of polyphenolic compounds during the composting of an olive-mill waste-wheat straw mixture by using quantitative (Folin-Ciocalteu) and qualitative (High Pressure Liquid Chromatography, HPLC) analyses.
View Article and Find Full Text PDFMental workload is a concept central to a range of disciplines (including cognitive psychology and ergonomics) that has given rise to various theoretical and methodological debates. As a result, researchers have used a number of techniques for measuring mental workload. Traditionally, three categories of measurement technique have been recognized: performance measures (e.
View Article and Find Full Text PDFThe main by-product generated by the Spanish olive oil industry, a wet solid lignocellulosic material called "alperujo" (AL), was evaluated as a composting substrate by using different aeration strategies and bulking agents. The experiments showed that composting performance was mainly influenced by the type of bulking agent added, and by the number of mechanical turnings. The bulking agents tested in this study were cotton waste, grape stalk, a fresh cow bedding and olive leaf; the latter showed the worse performance.
View Article and Find Full Text PDFOlive mill sludge (OMS), a by-product resulting from natural evaporation of olive oil processing effluent, poses a major environmental threat. A current cost-effective practice of OMS management is composting. A mixture of OMS (60%) with poultry manure (PM) was successfully composted for 210 days.
View Article and Find Full Text PDFOlive mill wastes represent a significant environmental problem in Mediterranean areas where they are generated in huge quantities in a short period of time. Their high phenol, lipid and organic acid concentrations turn them into phytotoxic materials, but these wastes also contain valuable resources such as a large proportion of organic matter and a wide range of nutrients that could be recycled. Composting is one of the technologies used for the valorization of this effluent, producing a fertilizer useful for poor soils.
View Article and Find Full Text PDFSludge from a sewage treatment plant dealing with the effluent produced during the processing of crude vegetable oil (Lesieur-Cristal, Morocco) was composted in two mixtures (M1 and M2) with household waste obtained from landfill. The different physico-chemical characteristics of the final composts after 5 months of composting were, for M1 and M2, respectively: pH: 8.5 and 7.
View Article and Find Full Text PDFThe co-composting of olive oil mill wastes and household refuse was followed for 5 months. During the thermophilic phase of composting, the aerobic heterotrophic bacteria (AHB) count, showed a significant rise with a slight regression of fungal biomass. In the same way, phospholipid fatty acids PLFAs common in bacteria, showed a significant increase of hydroxyl and branched PLFAs.
View Article and Find Full Text PDFWater-soluble extracts from compost may represent an alternative nutrient and organic matter source for crop production under drip irrigation. Dissolved organic matter (DOM), extracted from composted "alperujo", the main by-product from the Spanish olive oil industry, was applied to soil alone or in combination with either Glomus intraradices Schenck and Smith or a mixture of G. intraradices, Glomus deserticola (Trappe, Bloss.
View Article and Find Full Text PDFHow professional and novice designers manage multiple objectives through constraint satisfaction was studied. An objective is defined as a network of constraints; a constraint is characterized as related to a source (internal or external) and an addressee (e.g.
View Article and Find Full Text PDFA pot experiment was conducted on a low-fertility calcareous soil in order to evaluate the effect on ryegrass growth and nutrient uptake of an organic fertiliser obtained by composting "alperujo" and cotton gin waste. Compost, alone and combined with nitrogen fertilisation, was added to the soil at three rates and three harvests were obtained. The compost application enhanced plant growth in the first and third harvest.
View Article and Find Full Text PDFThe evaluation of the most suitable aeration technology for olive-mill by-product "alperujo" (AL) composting was carried out by using two identical piles prepared by mixing AL with a bulking agent (fresh cow bedding) and a mature compost (as inoculant). Forced ventilation was employed in conjunction with mechanical turning in one of the piles, whereas only mechanical turning was used in the other pile. These two treatment methods were evaluated by assessing process efficiency and end-product quality.
View Article and Find Full Text PDFOlive-mill wastes and by-products from the edible olive oil industry contain a high non-stabilised organic load, including organic acids, phenolic compounds and fats with antimicrobial and phytotoxic properties, which make them unsuitable for direct agricultural application. The most abundant olive-mill by-product in Spain is "alperujo" (AL), a solid material with a lack of consistency and low porosity due to its high water content and small particle size, which can be suitably composted by adding bulking agents. Six piles were prepared by mixing AL with cotton waste, grape stalk, olive leaf and fresh cow bedding, then successively composted, five of them managed by forced ventilation assisted by mechanical turning and the sixth only turned.
View Article and Find Full Text PDFA pollutant solid material called "alperujo" (AL), which is the main by-product from the Spanish olive oil industry, was composted with a cotton waste as bulking agent, and the compost obtained (ALC) was compared with a cattle manure (CM) and a sewage sludge compost (SSC) for use as organic amendment on a calcareous soil. The experiment was conducted with a commercial pepper crop in a greenhouse using fertigation. Composting AL involved a relatively low level of organic matter biodegradation, an increase in pH and clear decreases in the C/N and the fat, water-soluble organic carbon and phenol contents.
View Article and Find Full Text PDFThe suitability of olive mill wastewater (OMW) for composting was studied by the addition of this liquid waste to a mixture of cotton gin waste and sewage sludge, and its composting was compared with that of another pile of similar composition, but without olive mill wastewater. Both piles were composted by the Rutgers static pile system in a pilot plant. To study the effects of both composts on plant yield and soil properties, a plot experiment was carried out with Swiss chard (Beta vulgaris L.
View Article and Find Full Text PDFElemental, functional and spectroscopic analyses (FTIR, 13C-NMR) were performed to study fulvic acids of composted olive mill wastes plus cereal straw, in order to follow the maturity of the final product during composting. The extracted fulvic acids were characterized by high nitrogen, acidic functional group and phenolic hydroxyl contents that might have resulted from the high degree of humification and the synthesis of more condensed humic complexes. This was confirmed by a decrease of alcoholic and aliphatic structures and an increase of aromatic structures, as shown by the FTIR and 13C-NMR analyses.
View Article and Find Full Text PDFIntroduction of the two-phase centrifugation system for olive oil extraction during the early nineties in Spain has led to the generation of approximately four million tons per year of a solid olive-mill by-product called "alperujo" (AL). Agrochemical characterisation showed that AL has a high moisture content, slightly acidic pH values and a very high content of organic matter, mainly composed by lignin, hemicellulose and cellulose. It also has a considerable proportion of fats, proteins, water-soluble carbohydrates and a small but active fraction of hydrosoluble phenolic substances.
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