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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.

A new concept of a system for Combined Heat and Power generation is presented. The concept is based on hybrid use of two renewable energy sources, direct solar (thermodynamic solar) and biomass (indirect solar energy). Biomass combustion is conducted using a fluidized bed combustor. A second source of energy, given by the direct irradiation of the bed with a concentrated solar radiation, is integrated in the same system, using the fluidized bed as solar receiver. A Stirling engine converts heat into mechanical power. A Scheffler type mirror is adopted to allow irradiation of the system in a fixed focal point. Advantages of the proposed solution are illustrated and some preliminary results on the performance of the system, obtained with a simple model, are presented. The principal improvements with respect to existing systems of similar size and primary energy source are illustrated. The most important are the enhanced heat transfer processes that are realized with the help of the fluidized bed, and the possibility of continuous cogeneration during the day. Different working conditions are considered to estimate the contribution given by the burning of fuel, in presence as well as in absence of sun irradiation (as during the night). The distribution of energy shares among the different flux contributes is reported versus the amount of biomass burned per unit time. The results clearly demonstrate the advantage of coupling, in the same system, two sources for heat generation, thus maintaining the option of producing electricity without the supply of biomass fuel.

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.

In this paper we argue for the need to apply a cognitive approach to understand deep dynamics and determinants of technological evolutions. After examining main contributions from innovation studies to the conceptualization of innovation and change in complex socio-technical environments, we highlight the contribution coming from the application of the cognitive approach to evolutionary studies on technologies and we introduce the concept of technological memory as an interpretative tool to understand those changes. We discuss our hypothesis with reference to several observations carried out in different local contexts – Mexico, India and Italy – in relation to technological change in the water sector. In those cases deliberate attempts to substitute traditional technologies with modern ones led to interesting trajectories of change ranging from the collapse of old technologies to the development of multifaceted hybridization patterns. Tema. Journal of Land Use, Mobility and Environment, 2014: INPUT 2014 - Smart City: planning for energy, transportation and sustainability of the urban system

Laser Grooved Buried Contact (LGBC) solar cell technology is an attractive way for the production of solar cells designed to operate at one sun. Although LGBC cells can have higher efficiency when compared to standard screen-printed solar cells, a more complex manufacturing process is required, increasing their relative costs. In the FP6 EU funded project “Lab2Line,” screen print and LGBC solar cell processing techniques are hybridized in order to produce lower cost high efficiency solar cells processed on large area mono-crystalline wafers, using techniques scalable to industry. Two hybrid approaches have been considered: in the first, screen-print (SP) is applied for both rear and front contacts; in the second process SP is applied only to the rear and then electroless plating is used to form the front contacts. Both Lab2Line hybrid approaches offer high average efficiencies with a small performance distribution, while simultaneously presenting a more compact, cost effective option to production. The combination of SP techniques with LGBC processes and electroless plating has led to a maximum efficiency of 17.34% for the first process and 18% (17.44% average on 171 wafers) for the latter. Modules having such cells result in FF of 79.0% and efficiency of 17.0%. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 1660-1664

Landscape architectonic compositions that draw on the underlying landscape structure can function as a carrier for changing programmes, cultures, processes, etc. Precisely such an explicitly spatial design is required to foster the inclusive city, one that is not only socially just but also sensitive to the environment while allowing for and evoking diverse social and natural processes. The objective of an ‘inclusive city’ is often related to social issues, which might easily lead to the exclusion of ecological values; the opposite approach may prove equally exclusive. Inclusivity also means creating room for the unexpected. From a design point of view, this requires two underlying attitudes: a willingness to see any design assignment from different perspectives as well as a readiness to create sustainable, flexible and open designs. These two attitudes are inherent to landscape architecture, which traditionally prioritizes the site over the programme, and—because of the long term, time-based condition of the landscape—is forced to think in open-ended designs. In this paper we discuss a selection of graduation projects of the landscape architecture track at the TU Delft in order to illustrate how inclusivity is inherent to a complete understanding of landscape architecture. Four essential perspectives on analysis and design—perception, palimpsest, process and scale continuum—are discussed in order to reveal their capacity to serve as a basis for designing inclusive urban landscapes. Research in Urbanism Series, Vol. 6 (2020): Inclusive Urbanism: Advances in research, education and practice

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