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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.

{"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. 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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 articlw addresses an important challenge ahead the integration of the electricity generated by wave energy conversion technologies into the electric grid. Particularly, it looks into the role of wave energy within the day-ahead electricity market. For that the predictability of the theoretical power outputs of three wave energy technologies in the Danish North Sea are examined. The simultaneous and co-located forecast and buoy-measured wave parameters at Hanstholm, Denmark, during a non-consecutive autumn and winter 3-month period form the basis of the investigation.The objective of the study is to provide an indication on the accuracy of the forecast of i) wave parameters, ii) the normalised theoretical power productions from each of the selected technologies (Pelamis, Wave Dragon and Wavestar), and iii) the normalised theoretical power production of a combination of the three devices, during a very energetic time period.Results show that for the 12 to 36 hours time horizon forecast, the accuracy in the predictions (in terms of scatter index) of the significant wave height, zero crossing period and wave power are 22%, 11% and 68%, respectively; and the accuracy in the predictions of the normalised theoretical power outputs of Pelamis, Wave Dragon and Wavestar are 44%, 52% and 62%, respectively. The best compromise between forecast accuracy and mean power production results when considering the combined production of the three devices.

This abstract describes a project based, interdisciplinary course on applied superconductivity that was shared between four departments. The topic of the course was high temperature superconducting wind turbine generators. The students started by studying the problem at hand and then worked with mathematical modelling, small-scale prototype construction, and experimental testing. The course followed the CDIO ethos, where the students Conceived the problem at hand; Designed a solution; Implemented that solution both by construction and modeling; and finally Operated the constructed prototype and models.

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.

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