Search results for "conte"
showing 10 items of 10369 documents
Food-web structure and mercury dynamics in a large subarctic lake following multiple species introductions
2016
Summary The rate of non-native fish introductions into freshwater ecosystems has more than doubled during the past three decades, posing a serious threat to native biodiversity. Despite potential benefits for fisheries, little is known about how introduced species interact with native communities at the food-web level, or impact energy transfer dynamics and accumulation of contaminants in lake ecosystems. Here, we explored the trophic structure of a large, oligotrophic subarctic lake and assessed the trophic niche use and potential ecosystem-wide consequences of two introduced salmonid species: piscivorous lake trout (Salvelinus namaycush) and zooplanktivorous vendace (Coregonus albula). We…
Rocking of rigid block on nonlinear flexible foundation
2017
Abstract The two prime models used currently to describe rocking of rigid bodies, the Housner’s model and the Winkler foundation model, can capture some of the salient features of the physics of this important problem. These two models involve either null or linear interaction between the block and the foundation. Hopefully, some additional aspects of the problem can be captured by an enhanced nonlinear model for the base-foundation interaction. In this regard, what it is adopted in this paper is the Hunt and Crossley’s nonlinear impact force model in which the impact/contact force is represented by springs in parallel with nonlinear dampers. In this regard, a proper mathematical formulatio…
A Sequential Game Approach for Computation-Offloading in an UAV Network
2017
International audience; Small drones are currently emerging as versatile nascent technology that can be used in exploration and surveillance missions. However, most of the underlying applications require very often complex and time-consuming calculations. Although, the limited resources available onboard the small drones, their mobility, the computation delays and energy consumption make the operation of these applications very challenging. Nevertheless, computation-offloading solutions provide feasible resolves to mitigate the issues facing these constrained devices. In this context, we address in this paper the problem of offloading highly intensive computation tasks, performed by a fleet…
On the Use of a GPU-Accelerated Mobile Device Processor for Sound Source Localization
2017
Abstract The growing interest to incorporate new features into mobile devices has increased the number of signal processing applications running over processors designed for mobile computing. A challenging signal processing field is acoustic source localization, which is attractive for applications such as automatic camera steering systems, human-machine interfaces, video gaming or audio surveillance. In this context, the emergence of systems-on-chip (SoC) that contain a small graphics accelerator (or GPU), contributes a notable increment of the computational capacity while partially retaining the appealing low-power consumption of embedded systems. This is the case, for example, of the Sam…
Controversias en la transición del libro de texto en papel y electrónico a los contenidos digitales
2018
It is suggested that, given the economic and cultural scale that the book represents in our society, the layout of the paper and digital version will live together for a long time. Therefore, textbooks will suffer a very similar fate. The current change is focused on the transformation of textbooks in digital content with different formats and access routes. Through this process, we are studying the disputes that these changes cause, whereas they reflex the level of assimilation of the technological innovations on the part of citizens. By means of ethnographic strategies, we try to understand inductively how different educational agents are accepting such innovations. The centres that we ha…
Process-and context-sensitive research on academic knowledge practices
2007
The Contextual Activity Sampling System (CASS) methodology and CASS-Query tools have been developed for the investigation of learning and working practices. The CASS-methods and tools provide contextualized data that allow the analyzing and modeling of within-person changes across time. This paper describes a pilot study with 3G mobiles used by eight engineering students. Students answered questionnaires concerning their ongoing study projects, academic emotions, and collaboration, with a mobile phone five times a day for a period of two weeks (70 queries per person). Variation in their emotions were examined by time-series analysis. Students were also interviewed before and after the CASS-…
Applying Biomimicry to Cities: The Forest as Model for Urban Planning and Design
2021
International audience; The idea of applying biomimicry to cities is attracting increasing attention as a way of achieving sustainability. Undoubtedly the most frequently evoked natural model in this context is the forest, though it has not yet been investigated with any great scientific rigour. To overcome this lacuna, we provide: first, a justification of the model of the forest via what we call the arguments from “fittingness”, “scale”, and “complexity”; second, an exploration of various key innovations made possible by this model in the fields of urban planning, urban water systems, urban energy and transport systems, and urban food and nutrient systems.
A Systematic Review of the Hydrological, Environmental and Durability Performance of Permeable Pavement Systems
2021
Due to urbanization, large portions of vegetated territory have been replaced by waterproof surfaces. The consequences are greater outflows, lower infiltration, and lower evapotranspiration. Pavement systems made with permeable surfaces allow the infiltration of water, ensuring reduction of runoff volume. In this paper, the methods of analysis of the hydrological and environmental performance of the pavement systems are reviewed in the context of urban drainage and regarding their durability. The purpose is to present an overview of the studies published during the last decade in the field. The Pubmed and Web Science Core Collection electronic databases were used to conduct the scientific l…
Soil conservation and sustainable development goals(SDGs) achievement in Europe and central Asia: Which role for the European soil partnership?
2021
Abstract Voluntary soil protection measures are not sufficient to achieve sustainable soil management at a global scale. Additionally, binding soil protection legislation at national and international levels has also proved to be insufficient for the effective protection of this non-renewable natural resource. In 2012, the FAO Members established the Global Soil Partnership (GSP) with the mission to facilitate and contribute exchange of knowledge and technologies related to soils, and develop dialogue and raise awareness for the need to establish a binding global agreement for sustainable soil management. Moreover, region-specific aspects of implementation are considered and strengthened th…
Using Two-Level Context-Based Predictors for Assembly Assistance in Smart Factories
2020
The paper presents some preliminary results in engineering a context-aware assistive system for manual assembly tasks. It employs context-based predictors to suggest the next steps during the manufacturing process and is based on data collected from experiments with trainees in assembling a tablet. We were interested in finding correlations between the characteristics of the workers and the way they prefer to assemble the tablet. A certain predictor is then trained with correct assembly styles extracted from the collected data and assessed against the whole dataset. Thus, we found the predictor that best matches the assembly preferences.