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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.

{"references": ["M. Salamanca, F. Mondragon, J. R. Agudelo, P. Benjumea, and A. Santamaria, \"Variations in the chemical composition and morphology of soot induced by the unsaturation degree of biodiesel and a biodiesel blend,\" Combust. Flame, vol. 159, no. 3, pp. 1100\u20131108, 2012.", "P. Benjumea, J. R. Agudelo, and A. F. Agudelo, \"Effect of the degree of unsaturation of biodiesel fuels on engine performance, combustion characteristics, and emissions,\" Energy and Fuels, vol. 25, no. 1, pp. 77\u201385, 2011.", "A. A. Refaat, \"Correlation between the chemical structure of biodiesel and its physical properties,\" Int. J. Environ. Sci. Technol., vol. 6, no. 4, pp. 677\u2013694, 2009.", "H. K. Imdadul, H. H. Masjuki, M. A. Kalam, N. W. M. Zulkifli, M. Kamruzzaman, M. M. Shahin, and M. M. Rashed, \"Evaluation of oxygenated n-butanol-biodiesel blends along with ethyl hexyl nitrate as cetane improver on diesel engine attributes,\" J. Clean. Prod., vol. 141, pp. 928\u2013939, 2017.", "N. Yilmaz and A. Atmanli, \"Experimental assessment of a diesel engine fueled with diesel-biodiesel-1-pentanol blends,\" Fuel, vol. 191, pp. 190\u2013197, 2017.", "C. Pagliaro, \"A deeper look at diesel fuel,\" The Chemistry of the Diesel Engine, 2012. (Online). Available: https://chembloggreen1.wordpress.com/page/2/. )Accessed: 07-Nov-2017).", "O. Bennett, \"Biofuels,\" House Commons Libr., pp. 1\u20139, 2011.", "European Parliament, \"Directive 2009/28/EC of the European Parliament and of the Council of 23 April 2009,\" Off. J. Eur. Union, vol. 140, no. 16, pp. 16\u201362, 2009.", "Volkswagen Group, \"Biodiesel statement,\" 2010.\n[10]\tS. Schober and M. Mittelbach, \"Iodine value and biodiesel: Is limitation still appropriate?,\" Lipid Technol., vol. 19, no. 12, pp. 281\u2013284, 2007.\n[11]\tG. Knothe, \"Analyzing biodiesel: standards and other methods,\" J. Am. Oil Chem. Soc., vol. 83, no. 10, pp. 823\u2013833, 2006.\n[12]\tD. Rutz and R. Janssen, \"Overview and Recommendations on Biofuel Standards for Transport in the EU (Contribution to WP 3.2 and WP 5.5),\" Munchen, Germany, 2006.\n[13]\tL. F. Ramirez-Verduzco, J. E. Rodriguez-Rodriguez, and A. del Rayo Jaramillo-Jacob, \"Predicting cetane number, kinematic viscosity, density and higher heating value of biodiesel from its fatty acid methyl ester composition,\" Fuel, vol. 91, no. 1, pp. 102\u2013111, 2012.\n[14]\tA. Sch\u00f6nborn, \"Influence of the molecular structure of biofuels on combustion in a compression ignition engine,\" University College London, 2009.\n[15]\tB. Ham, R. Shelton, B. Butler, and P. Thionville, \"Calculating the lodine value for marine oils from fatty acid profiles,\" J. Am. Oil \u2026, no. 20, pp. 1445\u20131446, 1998.\n[16]\tM. J. Murphy, J. D. Taylor, and R. L. Mccormick, \"Compendium of Experimental Cetane Number Data,\" Natl. Renew. Energy Lab., no. August, pp. 1\u201348, 2004."]} Hardly any neat biodiesel satisfies the European EN14214 standard for compression ignition engine application. To satisfy the EN14214 standard, various additives are doped into biodiesel; however, biodiesel additives might cause other problems such as increase in the particular emission and increased specific fuel consumption. In addition, the additives could be expensive. Considering the increasing level of greenhouse gas GHG emissions and fossil fuel depletion, it is forecasted that the use of biodiesel will be higher in the near future. Hence, the negative aspects of the biodiesel additives will likely to gain much more importance and need to be replaced with better solutions. This study aims to satisfy the European standard EN14214 by blending the biodiesels derived from sustainable feedstocks. Waste Cooking Oil (WCO) and Animal Fat Oil (AFO) are two sustainable feedstocks in the EU (including the UK) for producing biodiesels. In the first stage of the study, these oils were transesterified separately and neat biodiesels (W100 & A100) were produced. Secondly, the biodiesels were blended together in various ratios: 80% WCO biodiesel and 20% AFO biodiesel (W80A20), 60% WCO biodiesel and 40% AFO biodiesel (W60A40), 50% WCO biodiesel and 50% AFO biodiesel (W50A50), 30% WCO biodiesel and 70% AFO biodiesel (W30A70), 10% WCO biodiesel and 90% AFO biodiesel (W10A90). The prepared samples were analysed using Thermo Scientific Trace 1300 Gas Chromatograph and ISQ LT Mass Spectrometer (GC-MS). The GS-MS analysis gave Fatty Acid Methyl Ester (FAME) breakdowns of the fuel samples. It was found that total saturation degree of the samples was linearly increasing (from 15% for W100 to 54% for A100) as the percentage of the AFO biodiesel was increased. Furthermore, it was found that WCO biodiesel was mainly (82%) composed of polyunsaturated FAMEs. Cetane numbers, iodine numbers, calorific values, lower heating values and the densities (at 15 oC) of the samples were estimated by using the mass percentages data of the FAMEs. Besides, kinematic viscosities (at 40 °C and 20 °C), densities (at 15 °C), heating values and flash point temperatures of the biomixture samples were measured in the lab. It was found that estimated and measured characterisation results were comparable. The current study concluded that biomixture fuel samples W60A40 and W50A50 were perfectly satisfying the European EN 14214 norms without any need of additives. Investigation on engine performance, exhaust emission and combustion characteristics will be conducted to assess the full feasibility of the proposed biomixture fuels.

The paper offers a foundation upon which to build a better approach to integrate archeology and cultural heritage into the policy dialogue for climate related migration, both internally to the United States and internationally. First, the paper provides a survey of the pillars of climate change policy, mitigation, adaptation, and loss and damage, and how cultural heritage, archeology, and historic preservation are addressed within these three areas. It then delves further into the active role the cultural heritage community has fostered within the United States and internationally to better inform climate policy and action. It does so in part by synthesizing the work of the Pocantico Working Group on Climate Migration and Cultural Heritage, an international network of cultural leaders, archeologists, and scholars. Finally, the paper presents next steps into effectively incorporating cultural considerations into policy and legal options for addressing internal migration and relocation in the context of climate change. It is the intent of this brief piece to offer a groundwork reading of current frameworks for cultural heritage and climate change policy upon which future scholars can and should build towards finding effective ways of including heritage in climate action at the national and international levels. At its core, climate change is the modern story of the human journey. It is a story about the looming reality of losing the very things that connect us to our past and the tangible and intangible cultural heritage assets that construct the contours of our identities today.

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

The dataset provided here belongs to Eslami et al. (2021) article. We suggest to refer to that article before using the data. The excel sheet contains the description of simulations as it relates to their drivers and forcings. Two types of forcing are considered in this study. The climatic and anthropogenic drivers. The Climatic or climate change driven forces are upstream discharge anomalies and downstream sea level rise. The anthropogenic forces are spatially-varying extraction-induced land subsidence and average riverbed level erosions driven by sediment starvation due to upstream dams and downstream sand mining. This excel file defines the simulation ID and the description (driving forces) of every simulation (including all the sensitivity analysis simulations). The actual data is in form of three different Python 2.7 dictionaries, saved in NumPy binary format (*.npy). The filenames are as SWI_Projections_pxx.npy (pxx can be p50, p90 or p100). P50/P90 refer to Spatial values of 50th/90th percentile of salinity in the dry season of the simulation year, and P100 (100th percentile) is basically the maximum salinity in during the dry season of the simulation year. The files can simply be read in a Python 2.7 platform with NumPy module installed. The line to read the data is: data = np.load(filename, allow_pickle=True).item() Each dictionary contains several keys, each representing the results of a simulation. Under every simulation, the results contain: x_grid : x-coordinates of a 2km x 2km grid projected and interpolated over the model [UTM 48N, m] y_grid : y-coordinates of a 2km x 2km grid projected and interpolated over the model [UTM 48N, m] s_grid : Salinity over a 2km x 2km grid projected and interpolated over the model [PSU] xy_utm : Easting & Northing [UTM 48N, m], at exact model grid points latlon : Latitude & Longitude at exact model grid points salinity : modelled salinity [PSU] at exact model grid points info : explaining the above information For further information and detailed background, you may refer to the following paper: Eslami, S.; Hoekstra, P.; Minderhoud, P. S. J.; Trung, N. N.; Hoch, J. M.; Sutanudjaja, E. H.; Dung, D. D.; Tho, T. Q.; Voepel, H. E.; Woillez, M.-N.; and van der Vegt, M.: Projections of salt intrusion in a mega-delta under climatic and anthropogenic stressors, Nat. Commun. Earth Environ.

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)