RISK ANALYSIS OF CROPPING SYSTEMS USING EXPERIMENTAL CROPPING SYSTEM-FERTILIZER DATA

Using 11 years of experimental crop yields by cropping systems and fertilizer level, a MOTAD frontier was developed. This analysis allowed yield, cost, and stability interactions arising from crop sequences to be implicitly included. Target-MOTAD, Safety-First, and undominated stochastic efficient systems were also compared.Research Methods/ Statistical Methods, Risk and Uncertainty,

Addressing Student Engagement During COVID-19: Secondary STEM Teachers Attend to the Affective Dimension of Learner Needs

This case study examines how a cohort of eleven induction secondary STEM teachers engaged learners during the onset of COVID-19 and their designs for student engagement given an online or blended teaching context in fall 2020. Participants attended a summer professional development workshop guided by trauma-informed teaching practices and learner engagement conceptual frameworks. Through the analysis of teacher artifacts and interviews, we identified dimensions of student engagement that teachers prioritized. Results indicate a marked increase in teachers’ attention to affective and social dimensions of learner engagement. We argue that teacher awareness and action in the affective domain of student engagement is critical during times of trauma

Film Through Marx, Our Contemporary

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Collaborative Product–Service Approach to Aviation Maintenance, Repair, and Overhaul. Part II: Numerical Investigations

This two-part paper proposes a new collaborative approach to airframe maintenance, repair, and overhaul (MRO). A quantitative model is introduced in Part I to represent the business relationships between original equipment manufacturers (OEMs) and MRO enterprises. In Part II, the presented model is used to assess potential financial benefits obtained by each of these stakeholders as a result of the collaboration. The quantitative model is built to capture the main dependencies between an independent MRO operating in South America and its interactions with three major airframe OEMs. Interviews were conducted with MRO and OEM professionals to identify the most impactful operational resources on MRO activities. Stakeholders with different characteristics in terms of production capacity, annual revenue, fleet size, and age are considered in the numerical studies to quantify the viability of the proposed collaborative business model in different scenarios. The obtained results show that optimal investment levels must be determined for each stakeholder to ensure the viability of the proposed collaborative business model, confirming the need for a quantitative method to aid service designers making decisions. This collaborative model contributes to the relatively scarce literature on the topic and promotes effective and structured collaboration between OEMs and MRO enterprises aiming at delivering higher added value to customers (operators)

A proposition of a manufactronic network approach for intelligent and flexible manufacturing systems

The XPRESS project introduces a completely new scalable concept of a manufactronic networked factory, which is composed by a co-ordinated team of specialized autonomous objects (Manufactrons), each knowing how to do a certain process optimally. This knowledge based concept integrated the complete chain: production configuration (decrease of ramp-up time of at least 50%), multi-variant production line (varying types and volumes on a single line) and 100% quality monitoring. The manufactronic networked architecture allows continuous process improvement, and will be able to anticipate and to respond to rapidly changing consumer needs, producing high-quality products in adequate quantities while reducing costs. This concept is demonstrated in the automotive, aeronautics and electrical industry but can be transferred to nearly all production processes

Effect factors for marine eutrophication in LCIA based on species sensitivity to hypoxia

Hypoxia is an important environmental stressor to marine species, especially in benthic coastal waters. Increasing anthropogenic emissions of nutrients and organic matter contribute to the depletion of dissolved oxygen (DO). Biotic sensitivity to low levels of DO is determined by the organisms’ ability to use DO as a respiratory gas, a process depending on oxygen partial pressure. A method is proposed to estimate an indicator of the intensity of the effects caused by hypoxia on exposed marine species. Sensitivity thresholds to hypoxia of an exposed ecological community, modelled as lowest-observed-effect-concentrations (LOEC), were compiled from literature for 91 benthic, demersal and benthopelagic species of fish, crustaceans, molluscs, echinoderms, annelids, and cnidarians, and converted to temperature-specific benthic (100 m depth) LOEC values. Species distribution and LOEC values were combined using a species sensitivity distribution (SSD) methodology to estimate the DO concentration at which the potentially affected fraction (PAF) of the community's species having their LOEC exceeded is 50% (HC50LOEC). For the purpose of effect modelling in Life Cycle Impact Assessment (LCIA), Effect Factors (EF [(PAF) m3 kgO2−1]) were derived for five climate zones (CZ) to represent the change in effect due to a variation of the stressor intensity, or EF = ΔPAF/ΔDO = 0.5/HC50LOEC. Results range from 218 (PAF) m3 kgO2−1 (polar CZ) to 306 (PAF) m3 kgO2−1 (tropical CZ). Variation between CZs was modest so a site-generic global EF of 264 (PAF) m3 kgO2−1 was also estimated and may be used to represent the average impact on a global ecological community of marine species exposed to hypoxia. The EF indicator is not significantly affected by the major sources of uncertainty in the underlying data suggesting valid applicability in characterisation modelling of marine eutrophication in LCIA

On Hokusai's great wave off Kanagawa: Localization, linearity and a rogue wave in sub-antarctic waters

International audienceThe Hokusai woodcut entitled The great wave off Kanagawa has been interpreted as an unusually large storm wave, likely to be classed as a rogue wave, and possibly generated from nonlinear wave dynamics (J. H. E. Cartwright and H. Nakamura, Notes Rec. R. Soc. 63, 119-135 (2009)). In this paper, we present a complementary discussion of this hypothesis, discussing in particular how linear and nonlinear mechanisms can both contribute to the emergence of rogue wave events. By making reference to the Great wave's simultaneous transverse and longitudinal localization, we show that the purely linear mechanism of directional focusing also predicts characteristics consistent with those of the Great wave. In addition, we discuss the properties of a particular rogue wave photographed on the open ocean in sub-Antarctic waters, which shows two-dimensional localization and breaking dynamics remarkably similar to Hokusai's depiction in the woodcut