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This study evaluate the effects of different types of agricultural systems and their managements on energy balance over 45-year period (1970–2015). Agricultural systems were (i) spring barley and (ii) winter wheat monocultures with different types of organic supply (straw incorporation, straw incorporation + green manuring, green manuring and control without organic supply) and (iii) Norfolk four-course system. Averaged across each half of study period, total energy inputs ranged between 10.2 GJ ha-1 year-1 for barley in Norfolk to 22.9 GJ ha-1 year-1 for wheat in monoculture with green manuring. The results indicate increase of indirect inputs in case of wheat and barley in Norfolk. The only system where the indirect input energy became lower was barley monoculture. Total energy outputs ranged between 198 GJ ha-1 year-1 for wheat in Norfolk to 88 GJ ha-1 year-1 for barley in monoculture. Norfolk system had higher output/input ratio than monocultures during whole study period. In almost all systems the effectiveness of energy use decreased during study period when comparing two halves. Yields of cereals throughout all systems were negatively dependent on energy input.

This study evaluate the effects of different types of agricultural systems and their managements on energy balance over 45-year period (1970–2015). Agricultural systems were (i) spring barley and (ii) winter wheat monocultures with different types of organic supply (straw incorporation, straw incorporation + green manuring, green manuring and control without organic supply) and (iii) Norfolk four-course system. Averaged across each half of study period, total energy inputs ranged between 10.2 GJ ha-1 year-1 for barley in Norfolk to 22.9 GJ ha-1 year-1 for wheat in monoculture with green manuring. The results indicate increase of indirect inputs in case of wheat and barley in Norfolk. The only system where the indirect input energy became lower was barley monoculture. Total energy outputs ranged between 198 GJ ha-1 year-1 for wheat in Norfolk to 88 GJ ha-1 year-1 for barley in monoculture. Norfolk system had higher output/input ratio than monocultures during whole study period. In almost all systems the effectiveness of energy use decreased during study period when comparing two halves. Yields of cereals throughout all systems were negatively dependent on energy input.

The paper presents a method for the decentralised solution of the optimal-power-flow (OPF) problem of large, interconnected power systems. The method decomposes the central OPF problem of a multiarea system into independent OPF subproblems, one for each area. The mathematical decomposition method is based on the decoupling of the first-order (KKT) conditions of the original system-wide OPF problem. The solutions of the OPF subproblems of the different areas are co-ordinated through a pricing mechanism until they converge to the system-wide OPF solution. The method requires no parameter tuning for reaching convergence or faster convergence. Results from the application of the method to several IEEE test systems are presented.

The paper presents a method for the decentralised solution of the optimal-power-flow (OPF) problem of large, interconnected power systems. The method decomposes the central OPF problem of a multiarea system into independent OPF subproblems, one for each area. The mathematical decomposition method is based on the decoupling of the first-order (KKT) conditions of the original system-wide OPF problem. The solutions of the OPF subproblems of the different areas are co-ordinated through a pricing mechanism until they converge to the system-wide OPF solution. The method requires no parameter tuning for reaching convergence or faster convergence. Results from the application of the method to several IEEE test systems are presented.

In the Czech Republic, as a follow-up, a consortium of research organizations and universities has decided to simulate selected stress tests’ scenarios, in station blackout (SBO) and the loss of ultimate heat sink (LoUHS), with the aim to verify the national stress report and to analyze time response of respective source term releases. These activities are carried out in the frame of the project prevention, preparedness, and mitigation of consequences of severe accident (SA) at Czech NPPs in relation to lessons learned from stress tests after Fukushima, financed by the Ministry of Interior. The Research Centre Rez has been working on a methods for estimation of leakages and consequences of releases (MELCOR) model for VVER1000 nuclear power plant (NPP) starting with a plant systems nodalization. The aim was to benchmark the MELCOR model with the validated TRAC/RELAP advanced computational engine (TRACE) model, first comparing the steady state and continuing in a long-term SBO plus another event until the beginning of the SA. The presented work is based on the previous paper from the ICONE 23rd Conference hosted in Japan. It focuses mainly on the comparison of the thermohydraulics of the two models created in MELCOR and TRACE codes as outcome of the “Fukushima project.” After that, preliminary general results of the SA progression showing the hydrogen production and the relocation phenomena will be shortly discussed. This scenario is considered closed after some seconds to the break of the lower head. It is important to note that this paper is a substantial update of a previous one (Mazzini et al., 2015, “Analyses of SBO Sequence of VVER1000 Reactor Using TRACE and MELCOR Codes,” 23rd International Conference on Nuclear Engineering (ICONE23)) and although it contains the same descriptive sections, all the results are new.

In the Czech Republic, as a follow-up, a consortium of research organizations and universities has decided to simulate selected stress tests’ scenarios, in station blackout (SBO) and the loss of ultimate heat sink (LoUHS), with the aim to verify the national stress report and to analyze time response of respective source term releases. These activities are carried out in the frame of the project prevention, preparedness, and mitigation of consequences of severe accident (SA) at Czech NPPs in relation to lessons learned from stress tests after Fukushima, financed by the Ministry of Interior. The Research Centre Rez has been working on a methods for estimation of leakages and consequences of releases (MELCOR) model for VVER1000 nuclear power plant (NPP) starting with a plant systems nodalization. The aim was to benchmark the MELCOR model with the validated TRAC/RELAP advanced computational engine (TRACE) model, first comparing the steady state and continuing in a long-term SBO plus another event until the beginning of the SA. The presented work is based on the previous paper from the ICONE 23rd Conference hosted in Japan. It focuses mainly on the comparison of the thermohydraulics of the two models created in MELCOR and TRACE codes as outcome of the “Fukushima project.” After that, preliminary general results of the SA progression showing the hydrogen production and the relocation phenomena will be shortly discussed. This scenario is considered closed after some seconds to the break of the lower head. It is important to note that this paper is a substantial update of a previous one (Mazzini et al., 2015, “Analyses of SBO Sequence of VVER1000 Reactor Using TRACE and MELCOR Codes,” 23rd International Conference on Nuclear Engineering (ICONE23)) and although it contains the same descriptive sections, all the results are new.

Abstract A forecast of transport activity, energy consumption and carbon dioxide emissions from transportation, carried out under ‘business as usual’ economic assumptions, is presented for the 10 countries of Central and Eastern Europe that have acquired the status of ‘accession countries’ to the European Union. Energy demand is projected under considerations of the dynamic evolution of transport modes and their use, the evolution of automotive fuel prices, which are assumed to gradually converge with Western European price levels within the current decade, and assumptions on efficiency improvements in all transport modes according to current technological trends and European regulations. The results, showing transportation energy demand to double and CO2 emissions to be 70% higher in 2030 compared to 2000, are compared with other published forecasts and discussed with a view to potential future energy and environmental impacts in these countries, outlining major policy implications.

Abstract A forecast of transport activity, energy consumption and carbon dioxide emissions from transportation, carried out under ‘business as usual’ economic assumptions, is presented for the 10 countries of Central and Eastern Europe that have acquired the status of ‘accession countries’ to the European Union. Energy demand is projected under considerations of the dynamic evolution of transport modes and their use, the evolution of automotive fuel prices, which are assumed to gradually converge with Western European price levels within the current decade, and assumptions on efficiency improvements in all transport modes according to current technological trends and European regulations. The results, showing transportation energy demand to double and CO2 emissions to be 70% higher in 2030 compared to 2000, are compared with other published forecasts and discussed with a view to potential future energy and environmental impacts in these countries, outlining major policy implications.

Spinel LiNi0.5Mn1.5O4 as one of the high-energy positive electrode materials for next generation Li-ion batteries has attracted significant interest due to its economic and environmental advantages. However, the sensitivity of this type of material upon short to long term ambient storage conditions and the impact on the electrochemical performances remains poorly explored. Nevertheless, this remains an important aspect for practical large-scale synthesis, storage and utilization. Herein, we study and compare the evolution of surface chemistry, bulk crystal structure and elemental content evolution and distribution of LiNi0.5Mn1.5O4 using a variety of characterization techniques including XPS and STEM-EDS-EELS, as well as electrochemical analysis. We show that Mn species dominate the outer surface (0–5 nm), while Ni and Li are preferentially located further away and in the bulk. The studied LiNi0.5Mn1.5O4 material is found to be stable, with minor changes in surface or bulk characteristics detected, even after 12 months of storage under ambient air conditions. The low surface reactivity to air also accounts for the minor changes to the electrochemical performance of the air-exposed LiNi0.5Mn1.5O4, compared to the pristine material. This study provides guidance for the appropriate storage, handling and processing of this high-performance cathode material.