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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

O ensaio coral como momento de aprendizagem : a prática coral numa perspectiva de educação musical

Figueiredo, Sergio Luiz Ferreira de January 1990 (has links)
O objetivo desta pesquisa é apresentar questões sobre educação musical na prática coral. O ensaio coral é um momento de aprendizagem. É no ensaio coral que o conhecimento musical é construfdo. No capítulo 1 o treinamento é abordado como uma parte do processo de aprendizagem. Durante o ensaio coral muitos treinamentos são Utilizados com o objetivo de promover a aprendizagem musical. O capítulo 2 trata do planejamento do ensaio. Existem três pontos fundamentais para o planejamento: organização, aplicação e avaliação. A organização do repertório e do ensaio, a aplicação de estratégias e a avaliação dos resultados são desenvolvidos neste capítulo. A aprendizagem de conceitos musicais através da prática coral é o assunto do capftulo 3. Ritmo, melodia e harmonia são apresentados como componentes básicos para o desenvolvimento de conceitos musicais. Exemplos do repertório coral mostram alguns pontos relacionados ao ritmo, melodia e harmonia. São apresentados exercícios com o objetivo de indicar solução para determinados problemas de forma progressiva e contextualizada A técnica vocal é apresentada no capitulo 4 como um recurso na aprendizagem coral. A função da técnica vocal é facilitar a realização musical. Exercícios são apresentados com o objetivo de conduzir os cantores à compreensão dos elementos vocais necessários para a prática coral. A Inter-relação conceitos musicais, técnica vocal e repertório é extremamente Importante e necessária para que haja contextualização dos Inúmeros aspectos envolvidos na prática coral.
62

Optimize Natural Ventilation and Thermal Mass in Residential Buildings to Achieve Thermal Comfort and Reduction of Energy Consumption in Hot Dry Climate

Mousli, Kindah <1982> 01 June 2016 (has links)
Using natural phenomena to reach indoor comfort has been known since early time and the oldest heritage architecture‘s and engineering of Middle East region, which has responded with such phenomena as well very good solutions special for hot-dry region (height temperature and radiation at summer and big variation between day and night temperature also between the hot summer and cool winter). This Architecture realized inside its houses optimum comfortable temperatures throughout nearly all the days of the yearlong. That was through equating with the volume adopting and the space taming with the different natural elements forces of the sun, atmosphere and climate as all which is common in these days as passive design strategies and reducing energy consumption . This research investigate the thermal mass and natural ventilation for traditional house (hot-dry region in Damascus) that gives high energy efficiency in providing cool indoor air through ventilation (single sided , cross ventilation) and envelope behavior, with the procedures of measurements combined with simulation program model, to improve Middle East new residential buildings through utilize combination of passive cooling and heating techniques. Natural ventilation in traditional building coupled with effects of massive construction and design assemble, provide thermal comfort (temperature control) over interior condition. This strategies are utilized to conserve energy in a hot-dry climate specially on middle east region as Damascus and other cities which have comfort traditional houses . The modern template applied by simulation program for traditional heating and cooling technique achieves thermal comfort related to occupant behavior and reduces energy consumption for new apartment of about 30-45% reduction of energy needs at Damascus, 20-35% at Cairo and 15-30% also at very hot dry climate as Riyadh.
63

Theoretical and Experimental Investigation into Stop-Band Properties of Sonic Crystals

Morandi, Federica <1987> January 1900 (has links)
The present work explores the theoretical basis of sound propagation through periodic media and provides experimental evidences of stop-band properties of sonic crystals, periodic arrays of scatterers immersed in air. In order to investigate the sound field generated by sonic crystals, three theoretical models are used. The band structures are analysed with the Plane Wave Expansion method, while the Multiple Scattering Theory is used to calculate the magnitude of the scattered sound field. The Finite Element analysis is used for both purposes and to provide a stronger bond between the calculations of the theoretical models and the experimental results. Experimental measurement campaigns are performed at the Open University, Milton Keynes (UK) and at the University of Bologna. The two laboratories offer different testing facilities, respectively an anechoic chamber and a large industrial hall. Three square unit cells are analysed, varying the lattice constant and/or the filling fraction in order to provide a correlation between the two experimental setups. Measurements are performed to assess the characteristics of the sound field transmitted and reflected from the arrays, posing a special attention to the contribution of side and top edge diffraction. The evanescent behaviour of modes inside the lattice has been investigated by carrying out Impulse Response measurements inside the crystal and testing, with an intensity probe, the components of the sound field that exit the crystal in the two main directions. Finally, standardised indices are calculated that allow to compare the screening performance of sonic crystals to those of common noise barriers. All measurements setups report coherent results among them and with respect to the theoretical calculations, representing a solid platform for further developments.
64

Development and Applications of Simulation Codes for Air-to-Water and Ground-Coupled Heat Pump Systems

Naldi, Claudia <1987> January 1900 (has links)
In this Thesis, new simulation codes for the evaluation of a heat pump system seasonal performance are presented. The codes apply to electric air-to-water and ground-coupled heat pump systems based on a vapor compression cycle, used for building heating, cooling and domestic hot water production. Numerical models are developed to simulate different kinds of air-to-water heat pumps by means of the bin-method. The models take into account the different operating modes of mono-compressor on-off, multi-compressor and inverter-driven heat pumps. The heat pump system seasonal performance is analyzed in terms of SCOP and SEER in relation to the thermal characteristics of the building, the climate of the location and the kind of heat pump control system. Furthermore, numerical codes for the hourly simulation of air-to-water heat pump systems are developed. The dynamic codes are implemented in the software MATLAB and apply to on-off and inverter-driven heat pumps for building heating, cooling and domestic hot water production, coupled with storage tanks and integrated by a gas boiler or electric heaters. The codes are used, in particular, to evaluate the seasonal performance and the primary energy consumption of the inverter-driven air-to-water heat pump employed in the retrofit of a residential building in Bologna (Italy). A code for the hourly simulation of ground-coupled heat pump systems is developed. The code, implemented in MATLAB, employs g-functions expressed in analytic form and applies to on-off and inverter-driven heat pumps, used for building heating and/or cooling. The whole system, composed by the heat pump and the coupled borehole heat exchanger field, can be simulated for several years. The code is applied to analyze the effects of the inverter and of the total length of the borehole field on the mean seasonal performance of a ground-coupled heat pump system designed for a residential house with dominant heating loads.
65

Optical Techniques for Experimental Tests in Microfluidics

Puccetti, Giacomo <1988> 01 June 2016 (has links)
This PhD dissertation deals with the use of optical, non-invasive measurement techniques for the investigation of single and two-phase flows in microchannels. Different experimental techniques are presented and the achieved results are critically discussed. Firstly, the inverse use of the micro Particle Image Velocimetry technique for the detection of the real shape of the inner cross-section of an optical accessible microchannel is shown by putting in evidence the capability of this technique to individuate the presence of singularities along the wetted perimeter of the microchannel. Then, the experimental measurement of the local fluid temperature using non-encapsulated Thermochromic Liquid Crystal particles is discussed. A deep analysis of the stability of the color of these particles when exposed to different levels of shear stress has been conducted by demonstrating that these particles can be used for simultaneous measurements of velocity and temperature in water laminar flows characterized by low Reynolds numbers (Re < 10). A preliminary experiment where the TLC thermography is coupled to the APTV method for the simultaneous measurement of the three-dimensional velocity and temperature distribution in a microchannel is shown. Finally, an experimental analysis of the different flow patterns observed for an adiabatic air-water mixture generated by means of a micro T-junction is discussed. The main air-water mixture features have been deeply observed in 195 different experimental conditions in which values of superficial velocity ranging between 0.01 m/s and 0.15 m/s for both the inlet flows (air and water) are imposed. The flow patterns of the air-water mixture are strongly influenced by the value of the water superficial velocity; on the contrary, the air superficial velocity plays a secondary role for the determination of the characteristics of the bubbles (i.e. length).
66

The effective duration of the autocorrelation function of a sound signal: calculation methods, relationship with cognitive models and relevance on the subjective preference theory

D’Orazio, Dario <1978> 13 April 2011 (has links)
No description available.
67

Nuove prospettive per la produzione energetica

Terzi, Luigi Andrea <1972> 25 June 2007 (has links)
No description available.
68

Experimental and Numerical Analysis of Gas Forced Convection through Microtubes and Micro Heat Exchangers

Yang, Yahui <1984> 24 May 2013 (has links)
The last decade has witnessed very fast development in microfabrication technologies. The increasing industrial applications of microfluidic systems call for more intensive and systematic knowledge on this newly emerging field. Especially for gaseous flow and heat transfer at microscale, the applicability of conventional theories developed at macro scale is not yet completely validated; this is mainly due to scarce experimental data available in literature for gas flows. The objective of this thesis is to investigate these unclear elements by analyzing forced convection for gaseous flows through microtubes and micro heat exchangers. Experimental tests have been performed with microtubes having various inner diameters, namely 750 m, 510 m and 170 m, over a wide range of Reynolds number covering the laminar region, the transitional zone and also the onset region of the turbulent regime. The results show that conventional theory is able to predict the flow friction factor when flow compressibility does not appear and the effect of fluid temperature-dependent properties is insignificant. A double-layered microchannel heat exchanger has been designed in order to study experimentally the efficiency of a gas-to-gas micro heat exchanger. This microdevice contains 133 parallel microchannels machined into polished PEEK plates for both the hot side and the cold side. The microchannels are 200 µm high, 200 µm wide and 39.8 mm long. The design of the micro device has been made in order to be able to test different materials as partition foil with flexible thickness. Experimental tests have been carried out for five different partition foils, with various mass flow rates and flow configurations. The experimental results indicate that the thermal performance of the countercurrent and cross flow micro heat exchanger can be strongly influenced by axial conduction in the partition foil separating the hot gas flow and cold gas flow.
69

Multi-objective optimization of microgas turbine recuperatos

Pieri, Stefano <1977> 25 June 2007 (has links)
No description available.
70

Application of evolutionary techniques to energy transfer efficiency in heat transfer problems and low consumption buildings

Pinto, Francesco <1978> 25 June 2007 (has links)
No description available.

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