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[en] In his speech on energy transition on 28 November last, the President of the Republic alerted us to the urgent need to 'develop more strongly the interconnections between France and the other European countries to improve our security of supply at lower cost'. While the issue of security of supply is very real, the fact remains that, in their current embryonic state, interconnections alone are not sufficient to ensure this security; worse, they are the source of new and unlikely blackout configurations
[fr]Lors de son allocution relative a la transition energetique, le 28 novembre dernier, le president de la Republique nous alertait sur l'urgence a 'developper plus fortement les interconnexions entre la France et les autres pays europeens pour ameliorer notre securite d'approvisionnement a moindre cout'. Si l'enjeu de la securite d'approvisionnement est bien reel, il n'en reste pas moins que dans leur fonctionnement embryonnaire actuel, les interconnexions ne peuvent suffire a elles seules a assurer cette securite; pire, elles sont a l'origine de nouvelles configurations de black-out improbables
[en] Energy efficiency can be considered as a central pillar of global warming mitigation, with important co-benefits, including productivity gains, resource conservation or national security. It is also a subject of controversy between engineers and economists, who have divergent conceptions of the notion of optimality that delineates energy efficiency potentials. Modern surveys hardly go back beyond the 1970s and do not fully explore the reasons and conditions for the persistent differences between economists' and engineers' views. This paper provides such a historical account, investigating the positioning of economic analysis in contrast to the technical expertise on key energy efficiency topics - the rebound effect, the energy efficiency gap, and green nudges, from the 19. century to the present day. It highlights the permanence and evolution in the relationship that economists have had with technical expertise. An extension of the current conceptual framework is finally provided to connect our historical findings with avenues for future research. (authors)
[en] The adaptive cruise control (ACC) system is currently one of the most common research topics in automotive industry. The ACC system tracks the velocity of preceding vehicle by adjusting the throttle angle and applying brake, whenever needed. This system is acknowledged for improving the fuel efficiency due to coordination between brake and throttle. Inappropriate switching between brake and throttle results in loss of energy that increases fuel consumption. To address aforesaid problem, novel coordinated switching controllers for the ACC system are proposed that enhances the fuel efficiency. Moreover, the proposed control strategies are compared for various traffic scenarios, and then, fuel economy is observed for the proposed control schemes. Fuel economy is investigated using switching control paradigm design; namely, the proportional–integral–derivative (PID) controller, adaptive proportional–integral–derivative (APID) controller, and fuzzy PID controller for actual nonlinear and linearized model of the ACC system for various traffic scenarios including stop and proposed control strategies are compared using performance indices for various traffic scenarios, such as CC, ACC, and ACC stop and go in order to show the validity of the design. Furthermore, the comparison among the PID, APID, and fuzzy PID control schemes is investigated to analyze fuel economy of the actual nonlinear CC and ACC system.
[en] To be effective, the energy transition cannot be achieved by national measures alone. It can only succeed if all decentralised actors embark on a transformation of urban housing, community facilities, mobility systems, food supply and, more generally speaking, the entire urban landscape. The city of Grande-Synthe was the French capital of biodiversity in 2010 (Natureparif). It has also been known since 2016 for its refugee camp (set up by Doctors Without Borders) and more recently due to its introduction of a guaranteed minimum social income. Grande-Synthe is an example of an organised evolution towards a more economical consumption and production of energies based on lower greenhouse gas emissions
[fr]Pour etre efficace, la transition energetique ne peut pas se contenter de mesures nationales. Elle ne peut reussir que si tous les acteurs decentralises s'engagent dans un processus de transformation qui touche a la fois l'habitat urbain, les equipements collectifs, les mobilites, l'alimentation et plus generalement l'organisation de la cite et de l'espace. La ville de Grande-Synthe dans le Nord, capitale francaise de la biodiversite en 2010 (Natureparif) et surtout connue depuis 2016 pour son camp de refugies (avec Medecins sans frontieres) et plus recemment par la mise en oeuvre d'un Revenu Minimum Social Garanti, est un exemple d'evolution maitrisee vers une consommation plus econome et une production d'energies moins emettrices de gaz a effet de serre
[en] This research examines the role of poverty and logistical operations under the circumstance of environmental deterioration with panel data of ASEAN states from 2007 to 2017. The system-generalized method of moments (GMM) was adopted due to the presence of endogeneity. The results indicate that poverty and logistical operations have significant and positive relationship with greater environmental degradation. Because poor people are not skilled, they have to consume natural resources in original and unsustainable way for their survival and profits, which results in greater level of deforestation. On another hand, lacking fuel-efficient/green vehicles and green practices in logistical operations of ASEAN countries, logistics activities mainly depend on fossil fuel consumption, which generates greater carbon emission, methane, and greenhouse emissions that can directly damage the environment and become a primary source of climate change. Therefore, reduction in environmental degradation can be achieved through reduction in poverty and encouraging renewable energy and green practices in logistical operations. In addition, this study also provides detailed policy implications to regulatory bodies and corporate sector in order to improve environmental sustainability through adoption of green practices and reduction in poverty.
[en] This paper employs a parallelized genetic algorithm in generating long-term bounded halo orbit and optimizing transfer trajectory from earth to it in the full ephemeris model. While the conventional gradient methods are lacking in precision as well as time-consuming, the parallel genetic algorithm (PGA) offers an access to large-scale computing based on the advanced hardware capability. A bounded halo orbit without any stationkeeping maneuver in five periods is obtained inside a defined pipe region in the ephemeris model. Transfer trajectory from earth to the obtained halo orbit is also investigated in this paper. By optimizing insertion impulses in the backward propagation and midcourse in the forward propagation, a transfer trajectory from earth to halo with least fuel consumption is generated. Furthermore, launch window is investigated based on the periodic variation about inclination of the injection point on the parking orbit. A mapping method from spatial space to subspace is introduced for solving the time delay and position deviation problem. The numerical method employed in this paper is of high accuracy based on large-scale computing capability as well as efficient without any analytical initial guess, which makes it extensive in designing these unstable libration point orbits.
[en] Canada is a signatory to the Paris Accord and has set a target of reducing its emissions by 30% from 2005 levels by 2030. The production, transportation and use of Canada's abundant and diverse natural resources are an important part of the Canadian economy. Because these activities are energy-intensive and given the country's size and latitude, energy plays an important role in Canada's economic activity and emissions profile
[fr]Le Canada est signataire de l'Accord de Paris et s'est fixe comme objectif de reduire ses emissions de 30 % d'ici 2030 par rapport aux niveaux de 2005. La production, le transport et l'utilisation des ressources naturelles abondantes et diversifiees du Canada constituent une part importante de l'economie canadienne. Comme ces activites sont tres energivores et compte tenu de la surface du pays et de sa latitude, l'energie joue un role important dans l'activite economique du Canada et son profil d'emissions
[en] Full text: Magnesium is one of the lightest structural metals. It has important applications in the automotive and aerospace industries, where the use of lightweight materials results in lower fuel consumption (decreasing the emission of pollutants and global warming). However, there are two major challenges to overcome: low melting point (~ 650 ° C) and high rate of corrosion and oxidation . Mg alloys are also potential for hydrogen storage in solid state (metallic hydrides). The MgH2 has the highest capacity (7.6 wt% of H) between reversible hydrides. The drawbacks are slow reaction kinetics, high operational temperatures, and poor air resistance (oxidation). The MgO layer forms a barrier which cannot be penetrated by hydrogen. Nanocomposites by mechanical alloying have been shown improved kinetics. But, severe plastic deformation (SPD) methods, such as equal channel angular pressing (ECAP) and cold rolling (CR), can be used to produce grain refinement in bulk forms. With lower surface/volume ratio and favorable textures these materials present better air resistance . The aim of this work was to study the oxidation properties of cast commercial pure magnesium processed by ECAP (room temperature, 25 mm/min, 1 pass) followed by CR (20 passes). Structural characterizations were carried out by XRD and SEM, and the oxidation properties by TG/DSC (under a mixture of 80% of O2/ 20% of N2). XRD patterns showed that SPD methods produced different preferred orientations in Mg, along (101) plan for ECAPed and (002) for rolled. The processing routes reflected on oxidation properties, and they can produce safer and with higher ignition point samples. References  Y. Chunmiao, et al. J. Hazardous Mat. 260, 707–714 (2013).  A. M. Jorge, et al. Int. J. Hydrogen Energy 39, 3810-3821 (2014). (author)
[en] We are committed to a zero-carbon Europe by 2050, free of fossil and nuclear energy. By its size, Europe has the means to achieve this. It has the capacity. These commitments will be met without resorting to the artifices of the carbon market
[fr]Nous nous engageons pour une Europe zero carbone en 2050, liberee des energies fossiles et nucleaires. Par sa taille, l'Europe en a les moyens. Elle en a la capacite. Ces engagements seront tenus sans recourir aux artifices du marche carbone
[en] Modern Telecom Sector is eventually facing exceptionally tough challenges because of continuous and unexpected increase in power density requirement for the communicating machinery and equipment. To fulfil the power requirements for the equipment, a significant architecture and an optimal technique must be introduced. In this paper, a microcontroller-based optimization use of power-density has been carried out. Meeting above requirements, various equipment and electronic devices are employed. We have designed a microcontroller-based system via PROTEUS Virtual System Modeling to acquire efficient and effective results. The main focus of our work is to supply the power to Telecom equipment in meantime. The power is feeding on batteries and DG (Diesel Generator) set, depending on the condition of the power requirements. The changeover operations are performed by different relays, which are dully programmed via a microcontroller in Keil software. The power capacity of Telecom ((Telecommunication) equipment is ranged from 39-48 Volts DC. The rectification process is done by switch mode rectifiers instead of linear rectifiers. Because the switch-mode rectifier technology has brought fabulous improvements in power density as compared to linear rectifiers. This is done via simulation of the smart switch in PROTEUS software. The outcomes of the proposed system are cost effective in terms of fuel consumption of DG. (author)