997 resultados para cultural flows


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The aim of this thesis was to research how slurry’s viscosity and rheology affect to pumping in peristaltic hose pump and in eccentric progressive cavity pump. In addition, it was researched the formed pressure pulsation in hose pump. Pressure pulsation was studied by pumping different slurries and by using different pipe materials. Pressure and power curves were determined for both used pumps. It was also determined NPSHR curve for the progressive cavity pump. Literature part of the thesis considered to distribute fluids to different rheology types, as well as theories and models to identify different rheology types. Special attention was paid to non-Newtonian fluids, which were also used in experimental part of this thesis. In addition, the literature part discusses about pumps, parameters for pump sizing, and pressure pulsation in hose pump. Starch, bentonite, and carboxymethyl cellulose slurries were used in the experimental part of this thesis. The slurries were pumped with Flowrox peristaltic hose pump (LPP-T32) and eccentric progressive cavity pump (C10/10). From the each slurry was taken a sample, and the samples were analyzed for concentration, viscosity and rheology type. The used pipe materials in pressure pulsation experiments were steel and elastic, and it was also used a prototype of pulsation dampener. The pulsation experiments indicated that the elastic pipe and the prototype of pulsation dampener attenuated pressure pulsation better than the steel pipe at low pressure levels. The differences between different materials disappeared when pressure level and pump rotation speed increased. In slurry experiments, pulsation was different depending on rheology and viscosity of the slurry. According to experiments, the rheology did not significantly affect to pump power consumption or efficiency.

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Este artigo trata do surgimento e transformação das categorias "iorubá" e "iorubidade" como atributos de importância coletiva para identidades sociais e práticas religiosas nos dois lados do Atlântico. Argumentando contra anacrônicas atribuições de origem feitas por acadêmicos, o artigo detalha como tais origens, identidades e religiões foram ativamente construídas na Nigéria, em Cuba e no Brasil durante o século vinte, através de processos etnogênicos e eclesiogênicos que envolviam interações complexas entre praticantes religiosos, etnógrafos e agentes do Estado, bem como mediações textuais e intertextualidades entre os gêneors etnográfico e hierográfico. O artigo conclui com um breve esboço da mais recente fase desse processo, marcado pela transformação do culto dos orixás em algo que se poderia descrever como um religião universal emergente.

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Wind energy has obtained outstanding expectations due to risks of global warming and nuclear energy production plant accidents. Nowadays, wind farms are often constructed in areas of complex terrain. A potential wind farm location must have the site thoroughly surveyed and the wind climatology analyzed before installing any hardware. Therefore, modeling of Atmospheric Boundary Layer (ABL) flows over complex terrains containing, e.g. hills, forest, and lakes is of great interest in wind energy applications, as it can help in locating and optimizing the wind farms. Numerical modeling of wind flows using Computational Fluid Dynamics (CFD) has become a popular technique during the last few decades. Due to the inherent flow variability and large-scale unsteadiness typical in ABL flows in general and especially over complex terrains, the flow can be difficult to be predicted accurately enough by using the Reynolds-Averaged Navier-Stokes equations (RANS). Large- Eddy Simulation (LES) resolves the largest and thus most important turbulent eddies and models only the small-scale motions which are more universal than the large eddies and thus easier to model. Therefore, LES is expected to be more suitable for this kind of simulations although it is computationally more expensive than the RANS approach. With the fast development of computers and open-source CFD software during the recent years, the application of LES toward atmospheric flow is becoming increasingly common nowadays. The aim of the work is to simulate atmospheric flows over realistic and complex terrains by means of LES. Evaluation of potential in-land wind park locations will be the main application for these simulations. Development of the LES methodology to simulate the atmospheric flows over realistic terrains is reported in the thesis. The work also aims at validating the LES methodology at a real scale. In the thesis, LES are carried out for flow problems ranging from basic channel flows to real atmospheric flows over one of the most recent real-life complex terrain problems, the Bolund hill. All the simulations reported in the thesis are carried out using a new OpenFOAM® -based LES solver. The solver uses the 4th order time-accurate Runge-Kutta scheme and a fractional step method. Moreover, development of the LES methodology includes special attention to two boundary conditions: the upstream (inflow) and wall boundary conditions. The upstream boundary condition is generated by using the so-called recycling technique, in which the instantaneous flow properties are sampled on aplane downstream of the inlet and mapped back to the inlet at each time step. This technique develops the upstream boundary-layer flow together with the inflow turbulence without using any precursor simulation and thus within a single computational domain. The roughness of the terrain surface is modeled by implementing a new wall function into OpenFOAM® during the thesis work. Both, the recycling method and the newly implemented wall function, are validated for the channel flows at relatively high Reynolds number before applying them to the atmospheric flow applications. After validating the LES model over simple flows, the simulations are carried out for atmospheric boundary-layer flows over two types of hills: first, two-dimensional wind-tunnel hill profiles and second, the Bolund hill located in Roskilde Fjord, Denmark. For the twodimensional wind-tunnel hills, the study focuses on the overall flow behavior as a function of the hill slope. Moreover, the simulations are repeated using another wall function suitable for smooth surfaces, which already existed in OpenFOAM® , in order to study the sensitivity of the flow to the surface roughness in ABL flows. The simulated results obtained using the two wall functions are compared against the wind-tunnel measurements. It is shown that LES using the implemented wall function produces overall satisfactory results on the turbulent flow over the two-dimensional hills. The prediction of the flow separation and reattachment-length for the steeper hill is closer to the measurements than the other numerical studies reported in the past for the same hill geometry. The field measurement campaign performed over the Bolund hill provides the most recent field-experiment dataset for the mean flow and the turbulence properties. A number of research groups have simulated the wind flows over the Bolund hill. Due to the challenging features of the hill such as the almost vertical hill slope, it is considered as an ideal experimental test case for validating micro-scale CFD models for wind energy applications. In this work, the simulated results obtained for two wind directions are compared against the field measurements. It is shown that the present LES can reproduce the complex turbulent wind flow structures over a complicated terrain such as the Bolund hill. Especially, the present LES results show the best prediction of the turbulent kinetic energy with an average error of 24.1%, which is a 43% smaller than any other model results reported in the past for the Bolund case. Finally, the validated LES methodology is demonstrated to simulate the wind flow over the existing Muukko wind farm located in South-Eastern Finland. The simulation is carried out only for one wind direction and the results on the instantaneous and time-averaged wind speeds are briefly reported. The demonstration case is followed by discussions on the practical aspects of LES for the wind resource assessment over a realistic inland wind farm.

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The objective of the present study was to translate the Kidney Disease Quality of Life - Short Form (KDQOL-SF™1.3) questionnaire into Portuguese to adapt it culturally and validate it for the Brazilian population. The KDQOL-SF was translated into Portuguese and back-translated twice into English. Patient difficulties in understanding the questionnaire were evaluated by a panel of experts and solved. Measurement properties such as reliability and validity were determined by applying the questionnaire to 94 end-stage renal disease patients on chronic dialysis. The Nottingham Health Profile Questionnaire, the Karnofsky Performance Scale and the Kidney Disease Questionnaire were administered to test validity. Some activities included in the original instrument were considered to be incompatible with the activities usually performed by the Brazilian population and were replaced. The mean scores for the 19 components of the KDQOL-SF questionnaire in Portuguese ranged from 22 to 91. The components "Social support" and "Dialysis staff encouragement" had the highest scores (86.7 and 90.8, respectively). The test-retest reliability and the inter-observer reliability of the instrument were evaluated by the intraclass correlation coefficient. The coefficients for both reliability tests were statistically significant for all scales of the KDQOL-SF (P < 0.001), ranging from 0.492 to 0.936 for test-retest reliability and from 0.337 to 0.994 for inter-observer reliability. The Cronbach's alpha coefficient was higher than 0.80 for most of components. The Portuguese version of the KDQOL-SF questionnaire proved to be valid and reliable for the evaluation of quality of life of Brazilian patients with end-stage renal disease on chronic dialysis.

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The objective of the present study was to translate, adapt and validate a Brazilian Portuguese version of the Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire. The study was carried out in two steps. The first was to translate the DASH into Portuguese and to perform cultural adaptation and the second involved the determination of the reliability and validity of the DASH for the Brazilian population. For this purpose, 65 rheumatoid arthritis patients of either sex (according to the classification criteria of the American College of Rheumatology), ranging in age from 18 to 60 years and presenting no other diseases involving the upper limbs, were interviewed. The patients were selected consecutively at the rheumatology outpatient clinic of UNIFESP. The following results were obtained: in the first step (translation and cultural adaptation), all patients answered the questions. In the second step, Spearman's correlation coefficients for interobserver evaluation ranged from 0.762 to 0.995, values considered to be highly reliable. In addition, intraclass correlation coefficients ranged from 0.97 to 0.99, also highly reliable values. Spearman's correlation coefficients and the intraclass correlation coefficients obtained during intra-observer evaluation ranged from 0.731 to 0.937 and from 0.90 to 0.96, respectively, being highly reliable values. The Ritchie Index showed a weak correlation with Brazilian DASH scores, while the visual analog scale of pain showed a good correlation with DASH score. We conclude that the Portuguese version of the DASH is a reliable instrument.

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Despite the complexity of the Chinese culture consumer product businesses should apply them in building brands for Chinese markets. There are reasons to believe that cultural values and attitudes affect the buying behavior of Chinese consumers. Companies that wish to create brands in China should therefore be aware of the prevailing cultural values and consumer attitudes. This thesis will examine which values and attitudes mostly affect Chinese consumers of health food products. The study will be done by conducting a netnography. Because netnography is actually a collection methods rather than a single method, other auxiliary methods will also be applied. These methods are emotion, language and sentiment analysis (ELS analysis). Emotion analysis will be conducted because cultural values are mostly built on emotional basis. Sentiment analysis will assist in recognizing the key factors that help to locate values and attitudes. Because the netnography will be conducted in Chinese web forums by a non-native researcher, linguistic aspects should also be analyzed in parallel with emotions and sentiment analysis. The study shows that the Chinese consumers of health food products put much importance on functional, analytical and collectivistic attitudes as well as social and psychological values. Of all the twelve cultural values defined, the role of family rose above all. Also perseverance, frugality, guanxi and harmony were highly presented. The attitudes were found by recognizing certain attitude factors. Of all the factors, health foods’ functional benefits and aesthetic content together with consumers’ value consciousness surpassed other factors. Besides these results that can be applied by foreign health food companies willing to enter Chinese consumer markets, also academia can benefit this new approach for conducting ethnographies online.

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This qualitative study has started from the interest to examine how the reality of crosscultural encounters is presented in the global business press. The research paper emphasizes different ways to classify culture and cross-cultural competency, both from the point of view of individuals and organizations. The analysis consists of public discourses, where cross-cultural realities are created through different persons, stories and contexts For data collection, a comprehensive database search was performed and 10 articles from the widely known worldwide business magazine The Financial Times were chosen as the data for the study paper. For the functions of addressing the research study questions, Thematic Content Analysis (TCA) and also Discourse Analysis (DA) are utilized, added with the continuous comparison method of grounded theory in the formation of the data.The academic references consist of literary works and articles presenting relevant concepts, creating a cross-cultural framework, and it is designed to assist the reader in the navigation through the topics of culture and cross-cultural competency. The repertoires were formed from the data and following, the first repertoire is contrast difference between home and target culture that the individual was able to discern. As a consequence of the first repertoire, the companies then offer cultural training to their employees to prepare them to situations of increasing levels of cultural variation. The third repertoire is increased awareness of other cultures, which is conveyed as a result of cultural training and contextual work experience. The fourth repertoire is globalization as an international business environment, where the people in the articles perform their job functions. It is stated in the conclusions that the representations emphasize Western values and personal traits in leadership.