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International audience Solar resource and forecasting in very short spatial and timescales (0–100 m, 0–30 min) is a challenging task that cannot be accurately achieved by satellite products or numerical weather predictions due to technical and methodological restrictions. For this reason, sky images from ground-based cameras are widely used during the last decade to deal with the high spatial and temporal variability of clouds and provide the needed inputs for numerical models for the current and forecasted (in short-term) solar irradiance. In this chapter, the available types of all-sky cameras/imagers are shortly presented. The chapter is focused on the state-of-the-art methodologies used to derive parameters needed for the estimations of solar resource and forecasting by a calibrated all-sky camera: cloud coverage, type, height, and velocity as well as aerosol optical properties. The application of these methodologies at Plataforma Solar de Almeria, in the frame of project: “Direct Normal Irradiance Nowcasting methods for optimized operation of concentrating solar technologies” (DNICast, http://www.dnicast-project.net/) is discussed. Finally, the chapter finishes with some propositions for future work in the recent, but quickly, developed research area.

Sustainability of agro-food supply chains has recently become the subject of greater interest from consumers, firms, governmental organizations and academia as the environment continues to deteriorate. One of the most critical factors influencing the sustainability of an agro-food supply chain is its network design. A particularly challenging aspect in this context is the broad range of influencing indicators associated with the Triple Bottom Line (TBL) of sustainability that need to be considered. However, many of these indicators could not be fully integrated or measured by single-step optimization problems. This paper presents a critical literature review of operational research methods for the design of sustainable supply chains. A novel two-stage hybrid solution methodology is proposed. In the first stage, a partner selection is performed using a hybrid multi criteria decision making based on Analytic Hierarchy Process (AHP) method and the Ordered Weighted Averaging (OWA) aggregation method. The result obtained in the first stage is used in the second stage to develop a multi-objective mathematical model to optimize the design of the supply chain network. This approach allows the simultaneous consideration of all three dimensions of sustainability including carbon footprint, water footprint, number of jobs created and the total cost of the supply chain design. The proposed approach generates a Pareto frontier to aid users in making decisions. Numerical experiments are completed utilizing data from an agro-food company to demonstrate the efficiency and effectiveness of the proposed solution methodology. The analyzes of the numerical results provide important organizational, practical and policy insights on (1) the impact of financial and environmental sustainability on supply chain network design (2) the tradeoff analysis between environmental emission, water footprint, societal implications and associated cost for making informed decision on supply chain investment.

Since the invention of fluorescent light sources, there is strong interest in Eu3+ activated phosphors as they are able to provide a high color rendering index (CRI) and luminous efficacy, which will also hold for phosphor converted light emitting diodes. Due to an efficient U6+ to Eu3+ energy transfer in Gd3Li3Te2O12:U6+,Eu3+, this inorganic composition shows red photoluminescence peaking at 611 nm. That means Eu3+ photoluminescence can be nicely sensitized via excitation into the U6+ excitation bands. Therefore, photoluminescence properties, such as temperature dependent emission and emission lifetime measurements, are presented. Charge transfer bands were investigated in detail. Additionally, density functional theory calculations reveal the band structure of the pure, i.e., non-doped host material. Obtained theoretical results were evaluated experimentally by the aid of diffuse UV reflectance spectroscopy.

Mixing under high pressure conditions plays a central role in several engineering applications, such as direct-injection engines and liquid rocket engines. Numerical flow simulations have become a complementary tool to study the mixing process under these conditions but require complex thermodynamic modeling as well as validation with accurate experimental data. For this reason, we use experiments of supercritical single-phase jet mixing from the literature, where the mixing is quantified by the mixture speed of sound, as a reference for our work. We here focus on the thermodynamic modeling of multi-component flows under high pressure conditions and the analytical calculation of the mixture speed of sound. Our thermodynamic model is based on cubic equations of state extended for multi-components. Using an extension of OpenFOAM, we perform large-eddy simulations of hexane and pentane injections and compare our results with the experimentally measured mixture speed of sound at specific positions. The simulation results show the same characteristic trends, indicating that the mixing effects are well reproduced in the simulations. Additionally, the effect of the sub-grid scale modeling is assessed by comparing results using different models (Smagorinsky, Vreman, and Wall-Adapting Local Eddy-viscosity). The comprehensive simulation data presented here, in combination with the experimental data, provide a benchmark for numerical simulations of jet mixing in high pressure conditions.

AbstractA large number of small- to medium-sized community ponds exist in most parts of the Terai region in Nepal. Such ponds could be a viable alternative for other forms of surface irrigation. But, with the lack of efficient management, many of these ponds remain underutilized. An effort was made to facilitate the rehabilitation of such a pond in a selected village of Rupandehi District in Western Terai region of Nepal. This paper aims to evaluate the changed water availability situation in post-monsoon seasons after the pond rehabilitation. The paper also evaluates the feasibility of such interventions especially focusing on the potential to provide additional water and improve agricultural productivity. Results showed small increases in quantifiable indicators such as water availability, cropping intensity, productivity and income. The new institutional setup improved water allocation, improved operation and maintenance, and increased social awareness among the people about the importance of underutilized water resources. The intervention has the potential to be replicated in similar contexts.

In 2010 the Vietnam government arrived at a decision to build the first nuclear power plant in the country Ninh Thuan 1 according to Russian project and with the help of Russian specialists. The construction of NPP in Vietnam will essentially relieve the deficit in energy production. The political leaders of Vietnam reckon upon the further growth of the economy. Energy of Vietnam is now generally held on big HPPs and TPPs. Small hydropower and such renewable energy sources as sun and wind play an important role in energy production. Because of the small amount of falls in the recent years in spite of monsoon climate, HPPs in Vietnam produce energy using not their full capacity. In TPP coal, diesel oil and gas is used as energy resources. The share of coal is still quite big (around 18 %) and coal TPPs have a serious negative impact on the environment. That’s why the specialists count on the development of nuclear energy. The paper presents the plans for the construction of a nuclear power plant "Ninh Thuan" in Vietnam, the alleged NPP project, its advantage over other projects, prerequisites and prospects for cooperation between the Russian and Vietnamese governments in this field.

This introductory article to the Ecological Modernization special issue begins with the observation that, when it comes to transitions, ecological modernization projects are often the ones being implemented. This justifies studying these projects in their own right. An analysis of what is involved in the concept of ecological modernization brings it back to the status of a promise, which is part of a relationship of both continuity and rupture with modernity. The articles in this issue are examined in light of this promise. These projects reveal the internal tensions within ecological modernization and show that, while it is continuously being renegotiated and hybridized, and despite suffering from significant internal limitations and criticisms, these projects appear to be united by their ability to strengthen the most powerful actors through compromises and minimal alignments. These compromises often lead to strong deviations from the promise and, ultimately, from the objectives of energy transition. Cet article introductif du numéro spécial Modernisation écologique part du constat qu’en matière de transition, ce sont le plus souvent des projets relevant de la modernisation écologique qui se mettent en œuvre – ce qui justifie que ces projets soient étudiés en tant que tels. Une analyse de ce que renferme l’idée de modernisation écologique renvoie celle-ci au statut de promesse, qui s’inscrit dans un rapport de continuité rupture par rapport à la modernité. Les articles réunis dans ce numéro sont lus à l’aune de cette promesse. Ces projets révèlent les tensions internes de la modernisation écologique, et montrent que si celle-ci est constamment renégociée et hybridée, si elle souffre d’importantes limites (et critiques) internes, ces projets semblent rassemblés par leur capacité à renforcer des acteurs les plus puissants autour de compromis et d’alignements a minima générant des écarts forts à la promesse et in fine aux objectifs de transition énergétique.