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The present research is dedicated to the study of anaerobic co-digestion process of different biomass materials. Anaerobic co-digestion of digested sludge, grass silage, haylage and cattle manure was evaluated in mesophilic tank reactors in the lab-scale experiment. Twelve laboratory scale tank reactors (1.5 L) were used during the incubation period of 45 days. First triplet of reactors was fed with pure digested sludge and the other three with different mixtures having the volumetric ratios of 30/35/25/10, 40/30/20/10 and 50/25/15/10 for digested sludge/corn silage/grass haylage/cattle manure. Methane production was analyzed for all labscale reactors individually. The resulting specific methane production of above-mentioned batches was 336.34, 238.1 and 233.23 LSTP[CH4] kg-1 [TVS], respectively. Other results such as cumulative biogas and methane yield, volumetric biogas and methane yield, volumetric biogas and methane yield per day were also assessed. These results had the highest meaning when complex substrate had no more than 30% of inoculum

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.

The utilization of biofuels in spark ignition and compression ignition engines is the trend of the recent time. The great expectations are inserted into n - butanol as a fuel, especially for spark ignition engines. The short time use of n - butanol in the SI (spark ignition) combustion engine does not make a big problem (start of the cold engine, change of the air - fuel ratio). The purpose of this contribution is the effect of long - term use of n - butanol as a fuel for SI engine. For this purpose the small portable generator was used. The harmful emissions, fuel consumption and power of the generator was measured then the generator was operated for 300 hours on 100% n - butanol with 80% of nominal load and the measurement was repeated. The g enerator was loaded with adjustable electrical resistance. As a reference fuel the petrol BA 95 with no bio - component was used. During the operation on n - butanol no technical problems occurred with the generator. After 300 hours of operation on n - butanol t he performance parameters slightly decreased with little impact on production of harmful emissions components.

The article deals with the issue of processing and utilization of citrus peel, which often ends unused with other biodegradable waste. The research is concerned with the energy potential of this raw material and its torrefaction conversion. The tested materials were orange peel (Citrus sinensis Osbeck cv 'Valencia', Citrus sinensis Osbeck cv 'Murcia') and grapefruit peel (Citrus paradise 'Ruby red'). Samples of dried materials underwent torrefaction treatment at 225 °C, 250 °C and 275 °C for 30 minutes. Samples before and after torrefaction were analysed for proximate and elemental composition and for calorific value. Consequently, stoichiometric combustion analyses were done. The torrefaction was performed in a LECO TGA 701 thermogravimetric analyzer under nitrogen atmosphere. The results of proximate and elemental analysis showed positive influence of torrefaction on the samples. The highest net calorific value for orange peel is 24.97 MJ kg-1 at the temperature of 275 °C. The greatest differences in net calorific values are between 225 °C and 250 °C where the increase is almost 3 MJ kg-1. Subsequently, the increase between the 250 °C and 275 °C torrefaction temperatures is 1 MJ kg-1. Weight loss at respective torrefaction temperatures showed similar time-dependent curves for all samples. Stoichiometric combustion analysis shows slight differences between original samples, but great differences after torrefaction processing. Stoichiometric combustion parameters also change proportionately with increasing temperature of torrefication. The resulting comnbustion balance figures show significantly lower need for mass of fuel in the case of the torrefied material for a given heat output thanks to the net calorific value being nearly doubled.

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

{"references": ["A. Zagoru\u013ako, K. Gerasimiva, and E. Altuncev, \"\u010cislennyj analiz\n\u0161\u010delevych uplotn\u011bnnij\", 12th International Scientific and Engineering\nconference (HERVICON 2008), Kielce-Przemysl, 9-12.September 2008.\npp. 105-113, ISSN 1897-2683.", "T. Staubi, and M. Bissing, \"Numerically calculated rotor dynamic\ncoefficients of a pump rotor side space\", Int. Symp. On Stability Control\nof Rotating Machinery (ISCORMA), South Lake Tahoe, August 2001.", "C. Z. Kundera, A. Korczak, A. Zahorulko, K. Gerasimiva, and M.\nPlykin, \"Numerical simulations of short and long annular seals\", Zeszyty\nNaukowy Politechniki \u0160wietokrzyskiej, serija Budowa I Eksploatacja\nMaszyn, Kielce, 2007. No.7, C.77-8.", "F. Pochyl\u00fd, J. Krutil, \"Hydrodynamic effects of the sealing gap\",\nResearch Report number VUT-EU QR-33-13, Brno university of\ntechnology, 2013.", "J. Krutil, F. Pochyl\u00fd, S. Fialov\u00e1, \"Matrices of additional effects of the\nhydrophilic sealing gap of the hydrodynamic machine\", Riadenie\ntekutinov\u00fdch syst\u00e9mov XIV. International scientific and technical\nconference \u2013 Tre\u010dianske Teplice, SK, 2014. pp. 88-91, ISSN 978-80-\n970897-8-8", "M. Athavale, and R. C. Hendricks, \"A small perturbation CFD method\nfor calculation of seal rotordynamics coefficients\", International Journal\nof Machinery, 1996, Vol. 2, No. 3., pp. 167-177.", "Y. Kanemori, and T. Iwatsobo, \"Experimental Study of Dynamics Fluid\nForces and Moments for a Long Annular seals\", ASME Journal of\nTribology, 1992, T.114, Oct., pp. 773-778."]} A mathematical model of the additional effects of the liquid in the hydrodynamic gap is presented in the paper. An incompressible viscous fluid is considered. Based on computational modeling are determined the matrices of mass, stiffness and damping. The mathematical model is experimentally verified.

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.