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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.
41

Josef Cheth Novotný - osobnost a dílo / Josef Cheth Novotný - personality and work

Drašnarová, Sylva January 2014 (has links)
This diploma thesis is the first biography about a journalist and writer Josef Novotný, who was born in Chrudim of 1900, considered one of the culturally liveliest Czech towns at the sunset of the 19th century. He engaged in writing as early as at grammar school, gaining first journalist experience in regional press, above all in Středostavovský buditel. This periodical was published by Československá živnostensko-obchodnická strana středostavovská. In the following years he worked as a reporter in Nová Praha, Trn, Tramp, Úl and others. In the 30s he started cooperation with Melantrich, where he wrote for České slovo and Český ilustrovaný zpravodaj. Later on in the late 40s he was employed as a reporter with Masarykův list. In 1948 his membership in Sydnikát českých novinářů had expired and by that literally his journalist career, too. He wrote tens of books, some of which were of autobiographic and regional character. He is the author of literature for children and youth, theatre and puppet plays, detective stories and rodokaps. He elaborated many historical themes and literary criticism essays. The biggest acknowledgement he received for his novel Piava based on his experiences from the frontline during the First World War. Most of his life work has never been published and is archived in the...
42

Pavel a Izrael podle epištoly Galatským / Paul and Israel in the Epistle to Galatians

Ženatý, Filip January 2012 (has links)
This paper deals with a question, how the apostle Paul saw the Christian church in relation to Israel as a people of God in the epistle to the Galatians. As it is an epistle written for a particular reason to the particular people, the first part of the paper deals with a brief analysis of the epistle as such and its context. The main part of the paper is focused on Paul's specific arguments. The role of Paul's conversion, his mission among the gentiles and his relationship with the Jerusalem authorities are evaluated at first. The paper clarifies also what the Antioch incident was about. What follows is the crucial analysis of the term "works of the Law", against which Paul places the faith alone. The paper subsequently focuses on the exposition of the role of Abraham in Paul's theological thoughts. How Paul saw the curse of the Law and how he understood the Jewish Law as such is examined as well. Paul's concept of the church as the newly redefined people of God is demonstrated on the idea of the freedom in the end.
43

A Numerical Study of Compressible Lid Driven Cavity Flow with a Moving Boundary

Hussain, Amer 13 May 2016 (has links)
A two-dimensional (2-D), mathematical model is adopted to investigate the development of circulation patterns for compressible, laminar, and shear driven flow inside a rectangular cavity. The bottom of the cavity is free to move at a specified speed and the aspect ratio of the cavity is changed from 1.0 to 1.5. The vertical sides and the bottom of the cavity are assumed insulated. The cavity is filled with a compressible fluid with Prandtl number, Pr =1. The governing equations are solved numerically using the commercial Computational Fluid Dynamics (CFD) package ANSYS FLUENT 2015 and compared with the results for the primitive variables of the problem obtained using in house CFD code based on Coupled Modified Strongly Implicit Procedure (CMSIP). The simulations are carried out for the unsteady, lid driven cavity flow problem with moving boundary (bottom) for different Reynolds number, Mach numbers, bottom velocities and high initial pressure and temperature.
44

Instabilidade hidrodinâmica linear do escoamento compressível em uma cavidade / Linear hidrodinamic instability of compressible lid-driven cavity flow

Bergamo, Leandro Fernandes 28 April 2014 (has links)
Os mecanismos de instabilidade hidrodinâmica têm um papel importante no processo da transição do escoamento de laminar para turbulento. A análise da instabilidade hidrodinâmica em uma cavidade com tampa deslizante foi realizada através da decomposição em modos globais (biglobal) para avaliar o efeito da compressibilidade neste fenômeno. O escoamento base foi obtido através de simulação numérica direta (DNS). Para tal, foi desenvolvido um código DNS compressível com discretização espacial por diferenças finitas compactas de alta resolução espectral e capacidade de processamento paralelo, com um método de decomposição de domínio que mantém a precisão das diferenças finitas compactas. O escoamento base é usado para montar o problema de autovalor oriundo das equações de Navier-Stokes linearizadas para a perturbação, discretizadas por diferenças finitas explícitas. O uso de diferenças finitas em conjunto com a implementação em matrizes esparsas reduz sensivelmente o uso de memória. Através do algoritmo de Arnoldi, a ordem do problema de autovalor é reduzida e os autovalores de interesse são recuperados. Os resultados indicam o efeito estabilizante da compressibilidade nos modos dominantes da cavidade e revelam modos inerentes ao escoamento compressível, para os quais a compressibilidade tem efeito desestabilizante. Dentre estes modos compressíveis, estão presentes modos de propagação sonora em dutos e modos relacionados à geração de som na cavidade. / Hydrodynamic instability mechanisms play an important role in laminar to turbulent transition. Hydrodynamic instability analysis of a lid-driven cavity flow was performed by global mode decomposition (biglobal) to evaluate compressibility effects on this phenomenon. The basic flow was calculated by direct numerical simulation (DNS). A compressible DNS code was developed with spectral-like compact finite difference spatial discretization. The code allows parallel processing with a domain decomposition method that preserves the compact finite difference accuracy. The basic flow is used to form the eigenvalue problem associated to the linear Navier- Stokes equations for the perturbation, which were discretized by an explicit finite difference scheme. The combination of sparse matrix techniques and finite difference discretization leads to a significant memory reduction. The order of the eigenvalue problem was reduced using the Arnoldi algorithm and the eigenvalues of interest were calculated. Results show the stabilizing effect of compressibility on the leading modes and reveal some modes intrinsic to compressible flow, for which compressibility has a destabilizing effect. Among these compressible modes, there are some related to sound propagation in ducts and to sound generation inside the cavity.
45

Instabilidade hidrodinâmica linear do escoamento compressível em uma cavidade / Linear hidrodinamic instability of compressible lid-driven cavity flow

Leandro Fernandes Bergamo 28 April 2014 (has links)
Os mecanismos de instabilidade hidrodinâmica têm um papel importante no processo da transição do escoamento de laminar para turbulento. A análise da instabilidade hidrodinâmica em uma cavidade com tampa deslizante foi realizada através da decomposição em modos globais (biglobal) para avaliar o efeito da compressibilidade neste fenômeno. O escoamento base foi obtido através de simulação numérica direta (DNS). Para tal, foi desenvolvido um código DNS compressível com discretização espacial por diferenças finitas compactas de alta resolução espectral e capacidade de processamento paralelo, com um método de decomposição de domínio que mantém a precisão das diferenças finitas compactas. O escoamento base é usado para montar o problema de autovalor oriundo das equações de Navier-Stokes linearizadas para a perturbação, discretizadas por diferenças finitas explícitas. O uso de diferenças finitas em conjunto com a implementação em matrizes esparsas reduz sensivelmente o uso de memória. Através do algoritmo de Arnoldi, a ordem do problema de autovalor é reduzida e os autovalores de interesse são recuperados. Os resultados indicam o efeito estabilizante da compressibilidade nos modos dominantes da cavidade e revelam modos inerentes ao escoamento compressível, para os quais a compressibilidade tem efeito desestabilizante. Dentre estes modos compressíveis, estão presentes modos de propagação sonora em dutos e modos relacionados à geração de som na cavidade. / Hydrodynamic instability mechanisms play an important role in laminar to turbulent transition. Hydrodynamic instability analysis of a lid-driven cavity flow was performed by global mode decomposition (biglobal) to evaluate compressibility effects on this phenomenon. The basic flow was calculated by direct numerical simulation (DNS). A compressible DNS code was developed with spectral-like compact finite difference spatial discretization. The code allows parallel processing with a domain decomposition method that preserves the compact finite difference accuracy. The basic flow is used to form the eigenvalue problem associated to the linear Navier- Stokes equations for the perturbation, which were discretized by an explicit finite difference scheme. The combination of sparse matrix techniques and finite difference discretization leads to a significant memory reduction. The order of the eigenvalue problem was reduced using the Arnoldi algorithm and the eigenvalues of interest were calculated. Results show the stabilizing effect of compressibility on the leading modes and reveal some modes intrinsic to compressible flow, for which compressibility has a destabilizing effect. Among these compressible modes, there are some related to sound propagation in ducts and to sound generation inside the cavity.
46

Life-Cycle-Cost Analysis of using Low Impact Development Compared to Traditional Drainage Systems in Arizona: Using Value Engineering to Mitigate Urban Runoff

January 2019 (has links)
abstract: The rate of urbanization has been impacted by global economic growth. A strong economy results in more people moving to already crowded urban centers to take advantage of increased employment opportunities often resulting in sprawling of the urban area. More natural land resources are being exploited to accommodate these anthropogenic activities. Subsequently, numerous natural land resources such as green areas or porous soil, which are less flood-prone and more permeable are being converted into buildings, parking lots, roads and underground utilities that are less permeable to stormwater runoff from rain events. With the diminishing of the natural landscape that can drain stormwater during a rainfall event, urban underground drainage systems are being designed and built to tackle the excess runoff resulting from urbanization. However, the construction of a drainage system is expensive and usually involves massive land excavations and tremendous environmental disturbances. The option for constructing an underground drainage system is even more difficult in dense urban environments due to the complicated underground environments, creating a need for low footprint solutions. This need has led to emerging opportunities for low impact development (LID) methods or green infrastructures, which are viewed as an environmentally friendly alternative for dealing with stormwater runoff. LID mimics the pre-development environment to retain the stormwater runoff through infiltration, retention, detention and evaporation. Despite a significant amount of prior research having been conducted to analyze the performance of runoff volume reduction and peak flow decrement of various green infrastructures, little is known about the economic benefits of using LID practices. This dissertation fills the gap in the knowledge regarding the life-cycle-cost effectiveness of green infrastructure in current urban developments. This study’s two research objectives are: (1) Develop a life cycle cost calculation template to analyze the cost benefits of using LID compared to the traditional drainage system (2) Quantify the cost benefits based on the real-world construction projects A thorough literature review led to the data collection of the hydrological benefits of using LIDs in conjunction with overviewing three real-world construction projects to quantify the cost benefits of LIDs. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2019
47

Numerical Investigation Of The Viscoelastic Fluids

Yapici, Kerim 01 July 2008 (has links) (PDF)
Most materials used in many industries such as plastic, food, pharmaceuticals, electronics, dye, etc. exhibit viscoelastic properties under their processing or flow conditions. Due to the elasticity of such materials, deformation-stress in addition to their hydrodynamic behavior differ from simple Newtonian fluids in many important respects. Rod climbing, siphoning, secondary flows are all common examples to how a viscoelastic fluid can exhibit quite distinctive flow behavior than a Newtonian fluid would do under similar flow conditions. In industrial processes involving flow of viscoelastic materials, understanding complexities associated with the viscoelasticity can lead to both design and development of hydrodynamically efficient processes and to improved quality of the final products. In the present study, the main objective is to develop two dimensional finite volume based convergent numerical algorithm for the simulation of viscoelastic flows using nonlinear differential constitutive equations. The constitutive models adopted are Oldroyd-B, Phan-Thien Tanner (PTT) and White-Metzner models. The semi-implicit method for the pressure-linked equation (SIMPLE) and SIMPLE consistent (SIMPLEC) are used to solve the coupled continuity, momentum and constitutive equations. Extra stress terms in momentum equations are solved by decoupled strategy. The schemes to approximate the convection terms in the momentum equations adopted are first order upwind, hybrid, power-law second order central differences and finally third order quadratic upstream interpolation for convective kinematics QUICK schemes. Upwind and QUICK schemes are used in the constitutive equations for the stresses. Non-uniform collocated grid system is employed to discretize flow geometries. As test cases, three problems are considered: flow in entrance of planar channel, stick-slip and lid driven cavity flow. Detailed investigation of the flow field is carried out in terms of velocity and stress fields. It is found that range of convergence of numerical solutions is very sensitive to the type of rheological model, Reynolds number and polymer contribution of viscosity as well as mesh refinement. Use of White-Metzner constitutive differential model gives smooth, non oscillatory solutions to much higher Weissenberg number than Oldroyd-B and PTT models. Differences between the behavior of Newtonian and viscoelastic fluids for lid-driven cavity, such as the normal stress effects and secondary eddy formations, are highlighted. In addition to the viscoelastic flow simulations, steady incompressible Newtonian flow of lid-driven cavity flow at high Reynolds numbers is also solved by finite volume approach. Effect of the solution procedure of pressure correction equation cycles, which is called inner loop, on the solution is discussesed in detail and results are compared with the available data in literature.
48

Análise da influência de variantes do método de solução de escoamentos utilizando os métodos de elementos finitos com compressibilidade artificial e pseudo-características

Oliveira, Marcos Paulo de Carvalho [UNESP] 31 August 2007 (has links) (PDF)
Made available in DSpace on 2016-04-01T17:54:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-31. Added 1 bitstream(s) on 2016-04-01T18:00:22Z : No. of bitstreams: 1 000505957.pdf: 1448129 bytes, checksum: ef6c3d75951b3a630e2efdba48bcb784 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O desenvolvimento de modelos numéricos para simulação de escoamentos tem se dado em diversos aspectos: desde os métodos de acoplamento entre pressões e velocidades até as técnicas de estabilização da solução. Neste contexto, este trabalho se propõe a implementar e avaliar o comportamento de um destes algoritmos, o CBS, utilizando-o na simulação de um escoamento isotérmico de fluido incompressível. Para tanto, foram utilizados variantes do esquema de solução com relação à discretização no tempo, com os métodos explícito e semi-implícito, além de algumas outras alterações na discretização no espaço e nos termos de estabilização. A discretização geral do problema foi feita com o método dos elementos finitos utilizando-se uma malha formada por elementos bilineares. O algoritmo e suas variações foram avaliados através de uma série de resultados, para diversos valores do número de Reynolds, de um problema clássico: a cavidade recirculante. Desta forma, foi possível mostrar que todas as variações da solução usando a malha estabelecida apresentaram concordância satisfatória com os resultados da literatura. Além disto, verificou-se que a omissão do termo característico não apresentou diferenças significativas nos resultados para os valores de número de Reynolds testados. Os resultados mostraram também que o método semi-implícito converge com um menor número de incrementos de tempo que o método explícito. / The development of numerical models for fluid flow simulation occurred at many aspects: since coupling methods between pressures and velocities until stabilization techniques. In this context, this work intends to implement and evaluate one algorithm behavior, the CBS, used in a simulation of incompressible and isothermal flows. This work also uses the explicit and semi-implicit methods of the time discretization scheme and some others changes in space discretization and stabilization terms for tests with algorithm. The discretization technique used is the finite element method with the mesh formed by bilinear elements. The algorithm's changes were evaluated using results for several Reynold's number in a classic problem: the lid-driven cavity. All the changes in solution algorithm with the used mesh show good agreement with other results from bibliography. It was verified too, that the omission of characteristics term didn't present significant differences in results with Reynold's number tested. It was observed yet that the solution code using the semi-implicit method converges with less time steps than the explicit one.
49

The cardiovascular and cerebrovascular effects of laryngoscopy and endotracheal intubation in neonatal piglets, and the modification of these effects by topical lignocaine

Belfort, M A 08 May 2017 (has links)
No description available.
50

Development of Treatment Train Techniques for the Evaluation of Low Impact Development in Urban Regions

Hardin, Mike 01 January 2014 (has links)
Stormwater runoff from urban areas is a major source of pollution to surface water bodies. The discharge of nutrients such as nitrogen and phosphorus is particularly damaging as it results in harmful algal blooms which can limit the beneficial use of a water body. Stormwater best management practices (BMPs) have been developed over the years to help address this issue. While BMPs have been investigated for years, their use has been somewhat limited due to the fact that much of the data collected is for specific applications, in specific regions, and it is unknown how these systems will perform in other regions and for other applications. Additionally, the research was spread across the literature and performance data was not easily accessible or organized in a convenient way. Recently, local governments and the USEPA have begun to collect this data in BMP manuals to help designers implement this technology. That being said, many times a single BMP is insufficient to meet water quality and flood control needs in urban areas. A treatment train approach is required in these regions. In this dissertation, the development of methodologies to evaluate the performance of two BMPs, namely green roofs and pervious pavements is presented. Additionally, based on an extensive review of the literature, a model was developed to assist in the evaluation of site stormwater plans using a treatment train approach for the removal of nutrients due to the use of BMPs. This model is called the Best Management Practices Treatment for Removal on an Annual basis Involving Nutrients in Stormwater (BMPTRAINS) model. The first part of this research examined a previously developed method for designing green roofs for hydrologic efficiency. The model had not been tested for different designs and assumed that evapotranspiration was readily available for all regions. This work tested this methodology against different designs, both lab scale and full scale. Additionally, the use of the Blaney-Criddle equation was examined as a simple way to determine the ET for regions where data was not readily available. It was shown that the methods developed for determination of green roof efficiency had good agreement with collected data. Additionally, the use of the Blaney-Criddle equation for estimation of ET had good agreement with collected and measured data. The next part of this research examined a method to design pervious pavements. The water storage potential is essential to the successful design of these BMPs. This work examined the total and effective porosities under clean, sediment clogged, and rejuvenated conditions. Additionally, a new type of porosity was defined called operating porosity. This new porosity was defined as the average of the clean effective porosity and the sediment clogged effective porosity. This porosity term was created due to the fact that these systems exist in the exposed environment and subject to sediment loading due to site erosion, vehicle tracking, and spills. Due to this, using the clean effective porosity for design purposes would result in system failure for design type storm events towards the end of its service life. While rejuvenation techniques were found to be somewhat effective, it was also observed that often sediment would travel deep into the pavement system past the effective reach of vacuum sweeping. This was highly dependent on the pore structure of the pavement surface layer. Based on this examination, suggested values for operating porosity were presented which could be used to calculate the storage potential of these systems and subsequent curve number for design purposes. The final part of this work was the development of a site evaluation model using treatment train techniques. The BMPTRAINS model relied on an extensive literature review to gather data on performance of 15 different BMPs, including the two examined as part of this work. This model has 29 different land uses programmed into it and a user defined option, allowing for wide applicability. Additionally, this model allows a watershed to be split into up to four different catchments, each able to have their own distinct pre- and post-development conditions. Based on the pre- and post-development conditions specified by the user, event mean concentrations (EMCs) are assigned. These EMCs can also be overridden by the user. Each catchment can also contain up to three BMPs in series. If BMPs are to be in parallel, they must be in a separate catchment. The catchments can be configured in up to 15 different configurations, including series, parallel, and mixed. Again, this allows for wide applicability of site designs. The evaluation of cost is also available in this model, either in terms of capital cost or net present worth. The model allows for up to 25 different scenarios to be run comparing cost, presenting results in overall capital cost, overall net present worth, or cost per kg of nitrogen and phosphorus. The wide array of BMPs provided and the flexibility provided to the user makes this model a powerful tool for designers and regulators to help protect surface waters.

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