• Energy Research
• DE close
• CN close
• FR close
• AT close
• Transport Research close

Underwater wireless sensor networks (UWSNs) widely used for maritime object detection or for monitoring of oceanic parameters that plays vital role prediction of tsunami to life-cycle of marine species by deploying sensor nodes at random locations. However, the dynamic and unpredictable underwater environment poses significant challenges in communication, including interference, collisions, and energy inefficiency. In changing underwater environment to make routing possible among nodes or/and base station (BS) an adaptive receiver-initiated deep adaptive with power control and collision avoidance MAC (DAWPC-MAC) protocol is proposed to address the challenges of interference, collisions, and energy inefficiency. The proposed framework is based on Deep Q-Learning (DQN) to optimize network performance by enhancing collision avoidance in a varying sensor locations, conserving energy in changing path loss with respect to time and depth and reducing number of relaying nodes to make communication reliable and ensuring synchronization. The dynamic and unpredictable underwater environment, shaped by variations in environmental parameters such as temperature (T) with respect to latitude, longitude, and depth, is carefully considered in the design of the proposed MAC protocol. Sensor nodes are enabled to adaptively schedule wake-up times and efficiently control transmission power to communicate with other sensor nodes and/or courier node plays vital role in routing for data collection and forwarding. DAWPC-MAC ensures energy-efficient and reliable time-sensitive data transmission, improving the packet delivery rati (PDR) by 14%, throughput by over 70%, and utility by more than 60% compared to existing methods like TDTSPC-MAC, DC-MAC, and ALOHA MAC. These enhancements significantly contribute to network longevity and operational efficiency in time-critical underwater applications.

Populations of fishes provide valuable services for billions of people, but face diverse and interacting threats that jeopardize their sustainability. Human population growth and intensifying resource use for food, water, energy and goods are compromising fish populations through a variety of mechanisms, including overfishing, habitat degradation and declines in water quality. The important challenges raised by these issues have been recognized and have led to considerable advances over past decades in managing and mitigating threats to fishes worldwide. In this review, we identify the major threats faced by fish populations alongside recent advances that are helping to address these issues. There are very significant efforts worldwide directed towards ensuring a sustainable future for the world's fishes and fisheries and those who rely on them. Although considerable challenges remain, by drawing attention to successful mitigation of threats to fish and fisheries we hope to provide the encouragement and direction that will allow these challenges to be overcome in the future.

Marine spatial planning (MSP) often favors blue growth objectives over biodiversity conservation, diminishing its role in promoting sustainability. We used in-depth qualitative document analysis to assess how conservation principles and priorities are included in five case studies to identify a path for better integrating conservation with MSP. Five themes emerged, reflecting conservation in MSP from weak to strong inclusion: (1) prioritizing economy; (2) ecosystems as limits; (3) social-ecological systems; (4) ecosystems as functional; and (5) ecosystems as fundamental. Our analysis suggests MSP priorities for managing or mitigating impacts and conservation was less apparent, though some plans appear more prepared to integrate conservation. We propose the concept of conservation ready MSP, where plans are designed to integrate conservation in MSP as a way to support sustained ocean use. MSP may

Abstract Speed variations are considered as an alternative for reducing fuel consumption during the use phase of passenger cars. It explores vehicle engine operating zones with lower fuel consumption, thus making possible a reduction in fuel consumption when compared to constant speed operation. In this paper, we present an evaluation of two conditions of speed variations: 50–70 km/h and 90–110 km/h using numerical simulations and controlled tests. The controlled tests performed on a test track by a professional pilot show that a reduction in fuel consumption is achievable with a conventional gasoline passenger car, with no adaptations for realizing speed variations. Numerical simulations based on a backward quasi-static powertrain model are used to evaluate the potential of speed variations for reducing fuel consumption in other speed variation conditions. When deceleration is performed with gear in neutral position, simulations show that speed variations are always correlated to a lower fuel consumption. This was suspected through previous numerical tests or evaluation on test bench but not in controlled tests conditions.

Le projet de loi de Finances pour 2014 (PLF 2014) a introduit une composante carbone dans la Taxe intérieure sur la consommation des produits énergétiques (TICPE) – appelée aussi contribution climat énergie ou encore taxe carbone. L’inscription de cette mesure dans le PLF 2014 revient au gouvernement, qui s’appuie formellement sur les travaux d’un Comité pour la fiscalité écologique (CFE) sur lesquels nous nous sommes penchée afin d’appréhender dans quelles conditions l’introduction de l’assiette carbone dans la TICPE a été élaborée. Sur cette base empirique (nombreux écrits du CFE et entretiens réalisés auprès de membres du comité), l’objet de cet article est de mettre en lumière une interdépendance entre fiscalité et politique énergétique que donne à voir le résultat de ces travaux, concrétisé par le vote de la réforme de la TICPE. Notre analyse met en lumière comment les membres du CFE ont dû s’accommoder des règles et formats imposés par la fiscalité. Ces règles fiscales se retrouvent en effet dans le choix de passer par la TICPE qui répond à une double injonction : d’une part, l’injonction de rendement – une taxe est avant tout une recette ; d’autre part, l’injonction de ne pas créer de nouvelle taxe. Le choix de réformer la TICPE comporte plusieurs caractéristiques porteuses de sens de politique publique. La mobilisation d’un instrument fiscal a conduit à s’appuyer sur des arguments de basculement de la fiscalité – une transition fiscale. Dans le même temps, se concentrer sur la consommation des énergies fossiles en introduisant la prise en considération des émissions de CO2 (y compris des carburants) a induit des échanges sur la recherche de sobriété en énergie – une transition énergétique. Bien entendu, la réalité ne choisit pas, mais au contraire, mixe les deux orientations, les rendant interdépendantes.