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We propose an on-the-fly statistical learning method to make a qualitative reduced-order model of the dynamics of a premixed flame quantitatively accurate. This physics- informed data-driven method is based on the statistically optimal combination of (i) a reduced-order model of the dynamics of a premixed flame with a level-set method, (ii) high-quality data, which can be provided by experiments and/or high-fidelity simulations, and (iii) assimilation of the data into the reduced-order model to improve the prediction of the dynamics of the premixed flame. The reduced-order model learns the state and the parameters of the premixed flame on the fly with the ensemble Kalman filter, which is a Bayesian filter used in the data assimilation of high-dimensional dynamical systems, e.g., in weather forecasting. The proposed method and algorithm are applied to two test cases with relevance to reacting flow and instability. First, the capabilities of the framework are demonstrated in a twin experiment, where the assimilated data are produced from the same model as that used in prediction. Second, the assimilated data are extracted from a high-fidelity reacting-flow direct numerical simulation (DNS). The results are analyzed by using Bayesian statistics, which provide the uncertainties of the calculations. This method opens up new possibilities for on-the-fly optimal calibration of computationally cheap reduced-order models when experimental data become available, for example, from sensors.

ON 16 NOVEMBER 2000, the final report of the World Commission on Dams (WCD) was launched in London, in the presence of South Africa’s former president Nelson Mandela. This represented a remarkable milestone in the history of dam policy and politics. During its two-year existence, WCD had conducted the most extensive review of research and evidence regarding the planning, impacts, and management of large dams. It had engaged with numerous stakeholders around the globe. It also made comprehensive recommendations about how to improve dam planning and management.

{"references": ["Kim H., Tadesse Y., Priya S., 2009, Energy Harvesting Technologies,\np3-4", "Curz Joao, 2008, Ocean Wave Energy, p1-4", "Zhu D., Beeby S., 2011, Energy Harvesting Systems, p1-3", "OECD, 2006, Energy Technology perspectives 2006: scenarios &\nstrategies to 2050, Organisation of Economic Cooperation &\nDevelopment, page 229-230.", "Khaligh A. and Onar Omer C., 2008, Energy Harvesting Solar, Wind, and\nOcean Energy Conversion System, pp223-230, pp250.", "Briney A., 2012, Waves - Ocean Waves, viewed at 10th April 2012,\n.", "Berteaux H. O., 1976, Buoy Engineering, The University of Michigan,\nUSA.", "Falnes, J 2007, \u00d4\u00c7\u00ffA review of wave-energy extraction-, ScienceDirect, vol.\n20, pp. 185-201", "Alaska Sea Grant, viewed at 16th April 2012,\n.\n[10] Robinson M. C., 2006, Renewable Energy Technologies for Use on the\nOuter Continental Shelf, National Renewable Energy Laboratory USA,\nviewed at 10th April 2012,\n.\n[11] Behrens, S, Heyward, J, Hemer, M, Osman, P 2011, \u00d4\u00c7\u00ffAssessing the wave\nenergy converter potential for Australian coastal regions-, Renewable\nEnergy, vol. 43, pp. 210-217.\n[12] Herbich, J 2000, Handbook of coastal engineering, Mcgraw-Hill\nprofessional.\n[13] Jefferys ER, 1980, Device characterization. In: Count BM (ed) Power\nfrom sea waves. Academic Press, pp 413-438."]} This paper presents an overview of the Ocean wave kinetic energy harvesting system. Energy harvesting is a concept by which energy is captured, stored, and utilized using various sources by employing interfaces, storage devices, and other units. Ocean wave energy harvesting in which the kinetic and potential energy contained in the natural oscillations of Ocean waves are converted into electric power. The kinetic energy harvesting system could be used for a number of areas. The main applications that we have discussed in this paper are to how generate the energy from Ocean wave energy (kinetic energy) to electric energy that is to eliminate the requirement for continual battery replacement.

{"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.

Over the past few years, remarkable developments in piezoelectric materials have motivated many researchers to work in the field of vibration energy harvesting by using piezoelectric beam like smart structures. This paper aimed to present the most recent application of a dual function piezoelectric device which can suppress vibration and harvest vibration energy simultaneously and a brief illustration of conventional mechanical and electrical TVAs (Tuned Vibration Absorber). It is shown that the proposed dual function device combines the benefits of conventional mechanical and electrical TVAs and reduces their relative disadvantages. Conversion of mechanical energy into electrical energy introduces damping and, hence, the optimal damping required by this TVA is generated by the energy harvesting effects. This paper presents the methodology of implementing the theory of 'electromechanical' TVAs to suppress the response of any real world structure. The work also illustrates the prospect of extensive applications of such novel "electromechanical" TVAs in defence and industry. The results show that the optimum degree of vibration suppression of an electronic box is achieved by this dual function TVA through suitable tuning of the attached electrical circuitry

One of the distinguishing features of the civil aero-engine market is its high competitiveness. The costs and risks associated with new projects are such that the difference between two apparently equally attractive options could result in success from one and a threat to the survival of the company from the other. To conceive and assess engines with minimum global warming impact and lowest cost of ownership in a variety of emission legislation scenarios, emissions taxation policies, fiscal and Air Traffic Management environments, a Techno-economic and Environmental Risk Assessment (TERA) model is needed. TERA incorporates multi-disciplinary modules for modelling gas turbine and aircraft performance, estimation of engine weight, noise and emissions as well as environment impact and operating economics. The TERA software is integrated with a commercial optimiser and provides a means for cycle studies. It is to be expected that new legislative and fiscal constraints on air travel will demand an extension to the customary range of asset management parameters. In such a business environment there is potential for TERA to develop into a useful tool for aircraft and engine asset management. This paper presents a description of this tool as well as gives some results from scenario studies.

Concerns about climate change, diminishing social acceptance of traditional fuels, and technological innovations have led several countries to pursue energy transition strategies, typically by massive diffusion of renewable electricity supplies. The German ‘Energiewende’ has been successful so far in terms of deploying renewable power, mainly by applying particular feed-in tariffs, and by bundling public, academic, industrial and political support. So far though, only few EU member states proceed with a similar transition. In March 2014 CEOs of Europe’s major energy companies publicly opposed a fast and thorough transformation of electricity supplies to become fully renewable. In April 2014 the European Commission published new state aid guidelines, generally mandating renewable energy support mechanisms (premiums, tenders) of lesser performance than regularly adjusted, specific feed-in tariffs. The new guidelines are likely to be pernicious for the fast deployment of renewable electricity supplies. In light of these challenges, this position paper highlights two implications of power sector transitions. First, the engineering-economics theory of power generation systems needs fundamental revision, mainly since a growing share of power sources no longer function on command. Second, and based on the experience in Germany, the paper sketches out a strategy for a thorough transition of the power sector, which, in the end, also entails normative judgements. Deep changes in energy systems and associated ways of living require societal consensus building based on ethical considerations. International Journal of Sustainable Energy Planning and Management, Vol 5 (2015)

{"references": ["H. C. Ong, T. M. I. Mahlia, H. H. Masjuki, \"A review on energy\nscenario and sustainable energy in Malaysia,\" Renewable and\nSustainable Energy Reviews, 1st issue, vol. 15, pp. 639-647, 2011.", "M. Bennet, and M. Newborough, \"Auditing energy use in cities,\"\nEnergy Policy, 2nd issue, vol. 29, pp. 125-134, 2001.", "L. P. Lombard, J. Ortiz, and C. Pout, \"A review on buildings energy\nconsumption information,\" Energy and Buildings, 3rd issue, vol. 40, pp.\n394-398, 2008.", "L. Jayamaha, \"Energy-efficient building systems,\" McGraw-Hill, 2007.", "J. E. Piper, \"Operations and maintenance manual for energy\nmanagement.- 1999. Quoted in W. Chung, Y. V. Hui, \"A study of\nenergy efficiency of private office buildings in Hong Kong,\" energy and\nBuildings, 6th issue, vol. 41, pp. 696-701, 2009.", "W. Y. Fung, W. T. Hung, S.W. Pang, and Y. L. Lee, \"Impact of urban\ntemperature on energy consumption,\" Energy, 14th issue, vol. 31, pp.\n2623-2367, 2006.", "S. A. Chan, \"Designing low energy buildings using Energy 10,\" 2004.", "C. Beggs, \"Energy management, supply and conservation,\" Elsevier,\n2nd ed., 2009.", "Gard Analytics, \"Types of energy audits,\" 2007.\n[10] S. Firth, K. Lomas, A. Wright, and R. Wall, \"Identifying trends in the\nuse of domestic appliances from household electricity consumption\nmeasurements,\" Energy and Buildings, 5th issue, vol. 40, pp. 926-936,\n2008."]} The increase in energy demand has raised concerns over adverse impacts on the environment from energy generation. It is important to understand the status of energy consumption for institutions such as Curtin Sarawak to ensure the sustainability of energy usage, and also to reduce its costs. In this study, a preliminary audit framework was developed and was conducted around the Malaysian campus to obtain information such as the number and specifications of electrical appliances, built-up area and ambient temperature to understand the relationship of these factors with energy consumption. It was found that the number and types of electrical appliances, population and activities in the campus impacted the energy consumption of Curtin Sarawak directly. However, the built-up area and ambient temperature showed no clear correlation with energy consumption. An investigation of the diurnal and seasonal energy consumption of the campus was also carried out. From the data, recommendations were made to improve the energy efficiency of the campus.