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Today the energy storage systems are still encumbering, therefore it is useful to think about the optimization of a railgun system in order to achieve the best performance with the lowest energy input. In this paper, an optimal design method considering 5 parameters is proposed to improve the energy conversion efficiency of a simple railgun. In order to avoid costly trials, the field- circuit method is employed to analyze the operations of different structural railguns with different parameters respectively. And the orthogonal test approach is used to guide the simulation for choosing the better parameter combinations, as well reduce the calculation cost. The research shows that the proposed method gives a better result in the energy efficiency of the system. To improve the energy conversion efficiency of electromagnetic rail launchers, the selection of more parameters must be considered in the design stage, such as the width, height and length of rail, the distance between rail pair, and pulse forming inductance. However, the relationship between these parameters and energy conversion efficiency cannot be directly described by one mathematical expression. So optimization methods must be applied to conduct design. In this paper, a rail launcher with five parameters was optimized by using orthogonal test method. According to the arrangement of orthogonal table, the better parameters’ combination can be obtained through less calculation. Under the condition of different parameters’ value, field and circuit simulation analysis were made. The results show that the energy conversion efficiency of the system is increased by 71.9 % after parameters optimization.

2nd generation biofuels gained more importance in recent years since they enable greenhouse gas emission reductions in the transport sector on a larger scale. One promising way to produce alternative fuels is the Biomass-to-Liquid (BtL) process with the Fischer-Tropsch synthesis which produces synthetic hydrocarbons that could directly be used as liquid fuels in an existing infrastructure. One major issue of this process is the production cost. Within the European COMSYN project (Compact Gasification and Synthesis process for Transport Fuels), a new BtL process concept is developed that aims to reduce biofuel production cost up to 35 % compared to alternative routes.

The functioning of food value chains entails a complex organisation from farm to fork which is characterised by various governance forms and externalities which have shaped the overall food system. VALUMICS food value chain case studies: wheat to bread, dairy cows to milk, beef cattle to steak, farmed salmon to fillets and tomato to processed tomato were selected to enable explorative and empirical analysis to better understand the functioning of the food system and, to identify the main challenges that need to be addressed to improve sustainability, integrity, resilience, and fairness of European food chains. The VALUMICS system analysis was executed through four operational phases starting with Groundwork & analysis including mapping specific attributes and impacts of food value chains and their externalities. This was followed by Case study baseline analysis, which provided input to the third phase on Modelling and exploration of future scenarios and finally Policy and synthesis of the overall work. This report is an overall synthesis of the VALUMICS results as follows: • Key findings from the VALUMICS project on the functioning of European food value chains and their impacts on more sustainable, resilient, fairer, and transparent food system are summarised through a compilation of 25 Research Findings and Policy Briefs. • By highlighting the major contributions from the research activities throughout the four phases of the VALUMICS project, this report delivers an assessment of various factors influencing sustainability, resilience, efficiency and fairness and effective chain relationships of different food value chains, and their determinants. • The synthesis of the outcome allows the identification of opportunities and challenges characterising the functioning of food supply chains, and thus, the prospects and potentials for strengthening the EU food sector. Citation: Olafsdottir, G., Bogason, S., Aubert, P.M., Barling, D., Thakur, M., Duric, I., Nicolau, M., McGarraghy, S., Sigurdardottir; H., Samoggia, A., Holden N.M., Čechura, L., Jaghdani, T.J., Svanidze, M., Esposito., G., Monticone, F., Fedato, C., Xhelili, A., Huber, E., Hargaden, V., Saviolidis, N M., Gorton, M., Hubbard, C., Kahiluoto, H., Hoang, V.(2021). Scenario analysis report with policy recommendations: An assessment of sustainability, resilience, efficiency and fairness and effective chain relationships in VALUMICS case studies. The VALUMICS project funded by EU Horizon 2020 G.A. No 727243. Deliverable: D8.4, University of Iceland, Reykjavík, 130 pages DOI:10.5281/zenodo.6534011

Sphagnum farming aims to produce peat moss fibres for horticultural growing media or founder material for bog restoration. The objective of this study was to examine the establishment of Sphagnum on cut-over bog with shallow layers (average 78 cm) of highly decomposed “black peat” under different hydrological starting conditions. One of the two study sites in northwestern Germany was established directly after peat extraction, while the other one has been rewetted 7 years prior to its installation. Irrigation ditches were installed on these sites for water management. Sphagnum fragments were introduced and covered with straw mulch or geotextile for protection. The establishment of Sphagnum and the site conditions, including vascular plant growth, were evaluated to determine the supporting and limiting factors for Sphagnum farming under the difficult hydrological conditions of shallow highly decomposed peat (low porosity, low hydraulic conductivity). The cultivation of Sphagnum mosses is possible on shallow layers of highly decomposed peat. Sphagnum growth in cover and carpet thickness was significantly higher at the site that had previously been rewetted and had a thicker layer of residual peat. The areas covered with a geotextile showed significantly lower percentages of Sphagnum cover compared to those covered with straw mulch. While sufficient water quantity and quality are known to be prerequisites for Sphagnum farming, a sufficient peat layer thickness seems to be an additional factor for successful Sphagnum establishment and growth. Maintaining an optimal water table proved to be a challenge for these shallow layers of highly decomposed peat, as the low hydraulic conductivity of the peat has impeded a complete irrigation of the sites. Furthermore, the irrigation effort might need to be increased to compensate for additional water loss into the subsoil. On such sites with difficult hydrological and soil conditions, a favourable microclimate provided by vascular plants and a rewetted surrounding area can promote successful establishment of Sphagnum and can even partially counterbalance effects of a low water table.

Contract-based nature protection schemes are a voluntary mechanism, with a limited contract duration, that aim to raise the acceptance of biodiversity conservation practices in agriculture among farmers and other land users. The purpose of this paper is to analyse the institutional settings of contract-based nature protection based on the��� ���Institutions of Sustainability��� (IoS) framework in the German Rhine-Sieg district, and to outline the way in which policy measures should be designed to encourage farmers to participate in contract-based nature protection programmes. This was achieved by answering research questions to identify the challenges, potentials and obstacles of a contract-based nature protection scheme in different ���sub-arenas��� as defined in the IoS framework. Qualitative research methods were used as the methodology. The analysis shows that main constraints for sufficient implementation of contract-based nature protection schemes are the limited consideration of the impact of climate change during the contract period, the limited consideration of regional conditions as regards the measures taken on the ground and an inflexible contract duration. International Journal on Food System Dynamics, Vol 13, No 1 (2022)

A measurement of the production of three isolated photons in proton–proton collisions at a centre-of-mass energy $\sqrt{s}$ = 8 TeV is reported. The results are based on an integrated luminosity of 20.2 fb$^{−1}$ collected with the ATLAS detector at the LHC. The differential cross sections are measured as functions of the transverse energy of each photon, the difference in azimuthal angle and in pseudorapidity between pairs of photons, the invariant mass of pairs of photons, and the invariant mass of the triphoton system. A measurement of the inclusive fiducial cross section is also reported. Next-to-leading-order perturbative QCD predictions are compared to the cross-section measurements. The predictions underestimate the measurement of the inclusive fiducial cross section and the differential measurements at low photon transverse energies and invariant masses. They provide adequate descriptions of the measurements at high values of the photon transverse energies, invariant mass of pairs of photons, and invariant mass of the triphoton system. Physics letters / B 781, 55 - 76 (2018). doi:10.1016/j.physletb.2018.03.057 Published by North-Holland Publ., Amsterdam

This paper examines how double exposure to both socio-economic and environmental stressors and the interaction between the two affect the population of the Northern coast of the São Paulo State, Brazil based on the conceptual and analytical framework developed by R. Leichenko and K.L. O’Brien. It provides a useful way to examine the multiple and overlapping processes of global change and, in particular, the places and the ways in which the economic and the non-economic interact. Interactions between economic and environmental change shape local landscapes of vulnerability and a major challenge for understanding vulnerability involves identifying how economic and environmental processes interact in particular places and how these interactions shape the effects of some global change processes and drive others. Pathways to increased vulnerability are multidimensional, so that socio-economic conditions may mediate the impacts of environmental change, but changing environmental conditions may also alter socio-economic capacities to maintain particular livelihood strategies. By analysing case studies of four municipalities that compound the region we found that people’s resilience, in general, are largely determined by the socio-economic context and the social vulnerability. Our finding indicate that socio-economic change brought about in the last three decades due to intense urbanization, tourism exploitation and increasingly economic activities have altered people’s livelihood and deepened social problems. We argue that the cross-scale nature of the problem and the cross-level interactions of these processes pose significant challenges for governance structures and institutions in place in the region that fail to address the roots of vulnerability and consequences of a changing environment.

The aim of the study was to determine the effects of nitrogen and phosphate fertilization on the growth performance of the novel bioenergy crop Fallopia sachalliensis cv. ‘Igniscum Candy’ (Polygonaceae). In a controlled pot experiment various nitrogen (0, 50, 150, 300 kg N ha-1) and phosphate (20, 40, 80 kg P ha-1) fertilizer amounts were applied to measure the effect on the biomass, height, leaf area and nitrogen and phosphate use efficiency. Furthermore, ecophysiological processes (chlorophyll content, chlorophyll fluorescence, gas exchange) were measured with non-destructive methods. The application of nitrogen correlated positively with biomass production, while phosphate fertilization did not show a significant effect on plant growth or ecophysiological parameters. The leaf nitrogen contents were significantly correlated with the nitrogen applications, while the leaf phosphate contents did not show a correlation with the P fertilizations, but increased with the leaf nitrogen contents. A significant linear correlation between the measured SPAD values and chlorophyll contents as well as with the leaf nitrogen contents could be determined. Under the influence of the nitrogen fertilization, net photosynthesis increased from 3.7 to 6.6 μmol m-2 s-1. The results of this experiment demonstrated that nitrogen fertilization has an overall positive correlation with leaf nutrient content, photosynthesis, and overall growth of the bioenergy crop Fallopia sachalinensis var. Igniscum Candy. Journal of Applied Botany and Food Quality, Vol 88 (2015), p.22-28