An efficient methodology based on two-and-a-half-dimensional finite element and boundary element methods for ground-borne vibration radiated by underground railway tunnels and the re-radiated noise emitted inside them

This thesis presents a methodology for assessing induced ground-borne vibration due to Underground railway infrastructures in the context of an urban environment. The methodology is based on a comprehensive numerical approach for modelling track/tunnel/soil systems considering a full-space model of the ground. This approach is formulated in the wavenumber-frequency domain and it is based on coupled finite element-boundary element method. An axisymmetric formulation to deal with circular underground railway tunnels is included in the approach in order to improve the computational speed of the methodology. This formulation can also be used for other types of railway tunnels if a circular boundary of the boundary element mesh is considered. The developed approach also includes asymptotic solutions of the Green's functions for large wavenumbers which results in an improvement of the accuracy of the overall methodology. A hybrid methodology which uses semi-analytical solutions of a cavity in a full-space in conjunction with the previously described approach has been developed with the aim of computing the energy flow radiated upwards by underground railway tunnels. Since this methodology uses finite elements to model the tunnel structure, its modelling detail is higher than the previously developed methodologies based on semi-analytical modelling of the tunnel structure. This hybrid methodology has been specifically designed for the study the vibration radiation of railway tunnels, the comparison between them and for the study of the insertion loss of mitigation measures at the sources, as soft rail-pads, under-ballast or under-slab mats, dynamics vibration absorbers, etc. In this thesis, this hybrid methodology is used to perform a comparison of the energy flow radiated upwards by various types of underground railway tunnels. Finally, a modelling approach for the re-radiated noise induced by a train passage inside railway tunnels is presented. This approach is based on the weak coupling between the comprehensive numerical approach for modelling track/tunnel/soil previously described and a two-and-a-half-dimensional boundary element method model for interior acoustics. Using this modelling approach, the influence of the fastener stiffness on the noise and vibration levels inside a simple tunnel as well as the relation between the noise emitted by the rails or the tunnel structure is investigated and discussed.Esta tesis presenta una metodología para evaluar la vibración inducida a través del terreno debido a infraestructuras ferroviarias soterradas en el contexto de un entorno urbano. La metodología se basa en un enfoque numérico integral para modelar sistemas de vía/túnel/terreno considerando un modelo de espacio completo del terreno. Este enfoque está formulado en el dominio de la frecuencia del número de onda y se basa en el método de los elementos finitos y el método de los elementos de contorno acoplados. Para mejorar la velocidad de cálculo de la metodología, se incluye una formulación axisimétrica para tratar túneles ferroviarios circulares. Esta formulación también se puede utilizar para otros tipos de túneles ferroviarios si se considera un contorno circular para la malla de elementos finitos. El enfoque desarrollado también incluye soluciones asimptóticas de las funciones de Green para grandes números de onda que resultan en una mejora de la exactitud de la metodología general. Se ha desarrollado una metodología híbrida que utiliza soluciones semi-analíticas de una cavidad en un espacio completo junto con el enfoque descrito anteriormente con el objetivo de calcular el flujo de energía de vibración radiado hacia arriba por túneles ferroviarias. Dado que esta metodología utiliza elementos finitos para modelar la estructura del túnel, su detalle de modelado es más alto que las metodologías desarrolladas anteriormente basadas en el modelado semi-analítico de la estructura del túnel. Esta metodología híbrida ha sido diseñada específicamente para el estudio de la radiación de vibración de túneles ferroviarios, la comparación entre ellos y para el estudio de la pérdida de inserción de medidas de mitigación, como suelas de baja rigidez, mantas bajo balasto o bajo losa, absorbentes de vibraciones dinámicos, etc. En esta tesis, esta metodología híbrida se utiliza para realizar una comparación del flujo de energía irradiado hacia arriba por varios tipos de túneles de ferrocarril subterráneo. Finalmente, se presenta un enfoque de modelado para el ruido re-irradiado inducido por un paso de tren dentro de los túneles ferroviarios. Este enfoque se basa en un acoplamiento débil entre el enfoque numérico integral para modelar el sistem vía/túnel/terreno descrito anteriormente y un modelo basado en método de los elementos de contorno 2.5D para la acústica interior del túnel. Usando este enfoque de modelado, se investiga y se discute la influencia de la rigidez de las fijaciones de carril en los niveles de ruido y vibración dentro de un túnel simple, así como la relación entre el ruido emitido por los carriles y la estructura del túnel.Postprint (published version

STUDY OF HbA1c AS A BIOMARKER IN DYSLIPIDEMIA AND ATHEROGENICITY IN TYPE 2 DIABETES MELLITUS

HbA1c is being used to assess the glycemic control for many years. This study was done to evaluate the importance of HbA1c in predicting dyslipidemia and atherogenecity in type 2 Diabetes. Methods: 200 type 2 diabetic patients were taken as subjects. Fasting and post meal blood sugar, Glycated haemoglobin (HbA1c), lipid profile, lipid ratios and atherogenic index of plasma(AIP) was analysed in these patients. The patients were divided into 2 groups depending on their HbA1c; Good Glycemic Control was defined as having HbA1c ≤ 7.0% and Poor Glycemic Control as HbA1c >7.0%. Results & Discussion: We found a significant increase in the levels of blood glucose, total serum cholesterol (TC), triglyceride, LDL cholesterol (LDL-C) and VLDL cholesterol (VLDL-C), TC/HDL-C, LDL-C/HDL-C, atherogenic index of plasma (AIP) and a significant decrease in the levels of HDL cholesterol (HDL-C) in patients with HbA1c >7% as compared to patients with HbA1c ≤ 7%. HbA1c had a direct and significant correlation with TC, TG, VLDL-C, LDL-C, TC /HDL-C, LDL-C/HDL-C, and an inverse correlation with HDL-C. AIP correlates with cardiovascular risk very well, and the association between HbA1c with various lipid parameters and atherogenic ratios suggests the importance of glycemic control in order to control dyslipidemia and future risk of cardiovascular disease in type 2 diabetics. KEYWORDS: Lipid profile; Type 2 diabetes mellitus; Glycosylated haemoglobin; Glycemic control, Atherogenic index of plasma

STUDY OF HbA1c AS A BIOMARKER IN DYSLIPIDEMIA AND ATHEROGENICITY IN TYPE 2 DIABETES MELLITUS

HbA1c is being used to assess the glycemic control for many years. This study was done to evaluate the importance of HbA1c in predicting dyslipidemia and atherogenecity in type 2 Diabetes. Methods: 200 type 2 diabetic patients were taken as subjects. Fasting and post meal blood sugar, Glycated haemoglobin (HbA1c), lipid profile, lipid ratios and atherogenic index of plasma(AIP) was analysed in these patients. The patients were divided into 2 groups depending on their HbA1c; Good Glycemic Control was defined as having HbA1c ≤ 7.0% and Poor Glycemic Control as HbA1c >7.0%. Results & Discussion: We found a significant increase in the levels of blood glucose, total serum cholesterol (TC), triglyceride, LDL cholesterol (LDL-C) and VLDL cholesterol (VLDL-C), TC/HDL-C, LDL-C/HDL-C, atherogenic index of plasma (AIP) and a significant decrease in the levels of HDL cholesterol (HDL-C) in patients with HbA1c >7% as compared to patients with HbA1c ≤ 7%. HbA1c had a direct and significant correlation with TC, TG, VLDL-C, LDL-C, TC /HDL-C, LDL-C/HDL-C, and an inverse correlation with HDL-C. AIP correlates with cardiovascular risk very well, and the association between HbA1c with various lipid parameters and atherogenic ratios suggests the importance of glycemic control in order to control dyslipidemia and future risk of cardiovascular disease in type 2 diabetics. KEYWORDS: Lipid profile; Type 2 diabetes mellitus; Glycosylated haemoglobin; Glycemic control, Atherogenic index of plasma

An efficient methodology based on two-and-a-half-dimensional finite element and boundary element methods for ground-borne vibration radiated by underground railway tunnels and the re-radiated noise emitted inside them

This thesis presents a methodology for assessing induced ground-borne vibration due to Underground railway infrastructures in the context of an urban environment. The methodology is based on a comprehensive numerical approach for modelling track/tunnel/soil systems considering a full-space model of the ground. This approach is formulated in the wavenumber-frequency domain and it is based on coupled finite element-boundary element method. An axisymmetric formulation to deal with circular underground railway tunnels is included in the approach in order to improve the computational speed of the methodology. This formulation can also be used for other types of railway tunnels if a circular boundary of the boundary element mesh is considered. The developed approach also includes asymptotic solutions of the Green's functions for large wavenumbers which results in an improvement of the accuracy of the overall methodology. A hybrid methodology which uses semi-analytical solutions of a cavity in a full-space in conjunction with the previously described approach has been developed with the aim of computing the energy flow radiated upwards by underground railway tunnels. Since this methodology uses finite elements to model the tunnel structure, its modelling detail is higher than the previously developed methodologies based on semi-analytical modelling of the tunnel structure. This hybrid methodology has been specifically designed for the study the vibration radiation of railway tunnels, the comparison between them and for the study of the insertion loss of mitigation measures at the sources, as soft rail-pads, under-ballast or under-slab mats, dynamics vibration absorbers, etc. In this thesis, this hybrid methodology is used to perform a comparison of the energy flow radiated upwards by various types of underground railway tunnels. Finally, a modelling approach for the re-radiated noise induced by a train passage inside railway tunnels is presented. This approach is based on the weak coupling between the comprehensive numerical approach for modelling track/tunnel/soil previously described and a two-and-a-half-dimensional boundary element method model for interior acoustics. Using this modelling approach, the influence of the fastener stiffness on the noise and vibration levels inside a simple tunnel as well as the relation between the noise emitted by the rails or the tunnel structure is investigated and discussed.Esta tesis presenta una metodología para evaluar la vibración inducida a través del terreno debido a infraestructuras ferroviarias soterradas en el contexto de un entorno urbano. La metodología se basa en un enfoque numérico integral para modelar sistemas de vía/túnel/terreno considerando un modelo de espacio completo del terreno. Este enfoque está formulado en el dominio de la frecuencia del número de onda y se basa en el método de los elementos finitos y el método de los elementos de contorno acoplados. Para mejorar la velocidad de cálculo de la metodología, se incluye una formulación axisimétrica para tratar túneles ferroviarios circulares. Esta formulación también se puede utilizar para otros tipos de túneles ferroviarios si se considera un contorno circular para la malla de elementos finitos. El enfoque desarrollado también incluye soluciones asimptóticas de las funciones de Green para grandes números de onda que resultan en una mejora de la exactitud de la metodología general. Se ha desarrollado una metodología híbrida que utiliza soluciones semi-analíticas de una cavidad en un espacio completo junto con el enfoque descrito anteriormente con el objetivo de calcular el flujo de energía de vibración radiado hacia arriba por túneles ferroviarias. Dado que esta metodología utiliza elementos finitos para modelar la estructura del túnel, su detalle de modelado es más alto que las metodologías desarrolladas anteriormente basadas en el modelado semi-analítico de la estructura del túnel. Esta metodología híbrida ha sido diseñada específicamente para el estudio de la radiación de vibración de túneles ferroviarios, la comparación entre ellos y para el estudio de la pérdida de inserción de medidas de mitigación, como suelas de baja rigidez, mantas bajo balasto o bajo losa, absorbentes de vibraciones dinámicos, etc. En esta tesis, esta metodología híbrida se utiliza para realizar una comparación del flujo de energía irradiado hacia arriba por varios tipos de túneles de ferrocarril subterráneo. Finalmente, se presenta un enfoque de modelado para el ruido re-irradiado inducido por un paso de tren dentro de los túneles ferroviarios. Este enfoque se basa en un acoplamiento débil entre el enfoque numérico integral para modelar el sistem vía/túnel/terreno descrito anteriormente y un modelo basado en método de los elementos de contorno 2.5D para la acústica interior del túnel. Usando este enfoque de modelado, se investiga y se discute la influencia de la rigidez de las fijaciones de carril en los niveles de ruido y vibración dentro de un túnel simple, así como la relación entre el ruido emitido por los carriles y la estructura del túnel

A methodology for the calculation of the noise radiated by the rails and the tunnel structure in railway tunnels

In this paper, a robust and fast numerical methodology to compute re-radiated noise in underground railway tunnels is proposed. In this study, the noise analysis does not account for the noise radiation from the train wheels, the rest of the rolling stock structure and the aerodynamic noise. The method is based on decoupled approach, where the acoustic and elastodynamic problems are solved separately on the assumption of weak coupling between the two subdomains. Two-and-a-half dimension (2.5D) finite element boundary element (FEM-BEM) is used to analyse the elastodynamic problem. The computation of the re-radiated noise from the vibration of the structure is done with a 2.5D acoustic boundary element method (BEM). The acoustic as well as elastodynamic BEM used in this analysis is based on globally regularized integrals based on singularity subtraction.Peer ReviewedPostprint (published version

The effect of tunnel construction on future underground railway vibrations

This paper investigates the effect of initial tunnel construction on the future ground vibration levels generated during underground railway line operation. This is important because tunnel construction results in soil disturbance, thus inducing high soil strain levels near the tunnel lining. The resulting soil stiffness degradation impacts the future generation of ground-borne traffic vibration and it's propagation to the foundations of nearby buildings, however has never been investigated. Therefore, to address this, this work develops a novel hybrid modelling approach, consisting of a construction simulation model and an elastodynamics model. First the convergence-confinement method is used to determine the stress state induced during tunnel construction using a tunnel boring machine (TBM). Next a 2.5D FEM-PML model consisting of vehicle-track-tunnel-soil is used to predict the vibration fields induced by underground trains. To link the approaches, the soil stiffness degradation contours computed from the tunnelling simulation act as inputs for the 2.5D underground railway model. This facilitates the assessment of the effect of tunnel construction on vibration levels. It is found that railway ground-borne vibration levels are underestimated if construction effects are ignored, with discrepancies of up to 10 dB found at higher frequencies. Therefore, when estimating future vibration levels during the underground railway design stage (e.g. for subway, metro, high-speed lines … etc), tunnel construction should be considered as an operational source of uncertainty

An efficient methodology based on two-and-a-half-dimensional finite element and boundary element methods for ground-borne vibration radiated by underground railway tunnels and the re-radiated noise emitted inside them

This thesis presents a methodology for assessing induced ground-borne vibration due to Underground railway infrastructures in the context of an urban environment. The methodology is based on a comprehensive numerical approach for modelling track/tunnel/soil systems considering a full-space model of the ground. This approach is formulated in the wavenumber-frequency domain and it is based on coupled finite element-boundary element method. An axisymmetric formulation to deal with circular underground railway tunnels is included in the approach in order to improve the computational speed of the methodology. This formulation can also be used for other types of railway tunnels if a circular boundary of the boundary element mesh is considered. The developed approach also includes asymptotic solutions of the Green's functions for large wavenumbers which results in an improvement of the accuracy of the overall methodology. A hybrid methodology which uses semi-analytical solutions of a cavity in a full-space in conjunction with the previously described approach has been developed with the aim of computing the energy flow radiated upwards by underground railway tunnels. Since this methodology uses finite elements to model the tunnel structure, its modelling detail is higher than the previously developed methodologies based on semi-analytical modelling of the tunnel structure. This hybrid methodology has been specifically designed for the study the vibration radiation of railway tunnels, the comparison between them and for the study of the insertion loss of mitigation measures at the sources, as soft rail-pads, under-ballast or under-slab mats, dynamics vibration absorbers, etc. In this thesis, this hybrid methodology is used to perform a comparison of the energy flow radiated upwards by various types of underground railway tunnels. Finally, a modelling approach for the re-radiated noise induced by a train passage inside railway tunnels is presented. This approach is based on the weak coupling between the comprehensive numerical approach for modelling track/tunnel/soil previously described and a two-and-a-half-dimensional boundary element method model for interior acoustics. Using this modelling approach, the influence of the fastener stiffness on the noise and vibration levels inside a simple tunnel as well as the relation between the noise emitted by the rails or the tunnel structure is investigated and discussed.Esta tesis presenta una metodología para evaluar la vibración inducida a través del terreno debido a infraestructuras ferroviarias soterradas en el contexto de un entorno urbano. La metodología se basa en un enfoque numérico integral para modelar sistemas de vía/túnel/terreno considerando un modelo de espacio completo del terreno. Este enfoque está formulado en el dominio de la frecuencia del número de onda y se basa en el método de los elementos finitos y el método de los elementos de contorno acoplados. Para mejorar la velocidad de cálculo de la metodología, se incluye una formulación axisimétrica para tratar túneles ferroviarios circulares. Esta formulación también se puede utilizar para otros tipos de túneles ferroviarios si se considera un contorno circular para la malla de elementos finitos. El enfoque desarrollado también incluye soluciones asimptóticas de las funciones de Green para grandes números de onda que resultan en una mejora de la exactitud de la metodología general. Se ha desarrollado una metodología híbrida que utiliza soluciones semi-analíticas de una cavidad en un espacio completo junto con el enfoque descrito anteriormente con el objetivo de calcular el flujo de energía de vibración radiado hacia arriba por túneles ferroviarias. Dado que esta metodología utiliza elementos finitos para modelar la estructura del túnel, su detalle de modelado es más alto que las metodologías desarrolladas anteriormente basadas en el modelado semi-analítico de la estructura del túnel. Esta metodología híbrida ha sido diseñada específicamente para el estudio de la radiación de vibración de túneles ferroviarios, la comparación entre ellos y para el estudio de la pérdida de inserción de medidas de mitigación, como suelas de baja rigidez, mantas bajo balasto o bajo losa, absorbentes de vibraciones dinámicos, etc. En esta tesis, esta metodología híbrida se utiliza para realizar una comparación del flujo de energía irradiado hacia arriba por varios tipos de túneles de ferrocarril subterráneo. Finalmente, se presenta un enfoque de modelado para el ruido re-irradiado inducido por un paso de tren dentro de los túneles ferroviarios. Este enfoque se basa en un acoplamiento débil entre el enfoque numérico integral para modelar el sistem vía/túnel/terreno descrito anteriormente y un modelo basado en método de los elementos de contorno 2.5D para la acústica interior del túnel. Usando este enfoque de modelado, se investiga y se discute la influencia de la rigidez de las fijaciones de carril en los niveles de ruido y vibración dentro de un túnel simple, así como la relación entre el ruido emitido por los carriles y la estructura del túnel

An efficient methodology based on two-and-a-half-dimensional finite element and boundary element methods for ground-borne vibration radiated by underground railway tunnels and the re-radiated noise emitted inside them

This thesis presents a methodology for assessing induced ground-borne vibration due to Underground railway infrastructures in the context of an urban environment. The methodology is based on a comprehensive numerical approach for modelling track/tunnel/soil systems considering a full-space model of the ground. This approach is formulated in the wavenumber-frequency domain and it is based on coupled finite element-boundary element method. An axisymmetric formulation to deal with circular underground railway tunnels is included in the approach in order to improve the computational speed of the methodology. This formulation can also be used for other types of railway tunnels if a circular boundary of the boundary element mesh is considered. The developed approach also includes asymptotic solutions of the Green's functions for large wavenumbers which results in an improvement of the accuracy of the overall methodology. A hybrid methodology which uses semi-analytical solutions of a cavity in a full-space in conjunction with the previously described approach has been developed with the aim of computing the energy flow radiated upwards by underground railway tunnels. Since this methodology uses finite elements to model the tunnel structure, its modelling detail is higher than the previously developed methodologies based on semi-analytical modelling of the tunnel structure. This hybrid methodology has been specifically designed for the study the vibration radiation of railway tunnels, the comparison between them and for the study of the insertion loss of mitigation measures at the sources, as soft rail-pads, under-ballast or under-slab mats, dynamics vibration absorbers, etc. In this thesis, this hybrid methodology is used to perform a comparison of the energy flow radiated upwards by various types of underground railway tunnels. Finally, a modelling approach for the re-radiated noise induced by a train passage inside railway tunnels is presented. This approach is based on the weak coupling between the comprehensive numerical approach for modelling track/tunnel/soil previously described and a two-and-a-half-dimensional boundary element method model for interior acoustics. Using this modelling approach, the influence of the fastener stiffness on the noise and vibration levels inside a simple tunnel as well as the relation between the noise emitted by the rails or the tunnel structure is investigated and discussed.Esta tesis presenta una metodología para evaluar la vibración inducida a través del terreno debido a infraestructuras ferroviarias soterradas en el contexto de un entorno urbano. La metodología se basa en un enfoque numérico integral para modelar sistemas de vía/túnel/terreno considerando un modelo de espacio completo del terreno. Este enfoque está formulado en el dominio de la frecuencia del número de onda y se basa en el método de los elementos finitos y el método de los elementos de contorno acoplados. Para mejorar la velocidad de cálculo de la metodología, se incluye una formulación axisimétrica para tratar túneles ferroviarios circulares. Esta formulación también se puede utilizar para otros tipos de túneles ferroviarios si se considera un contorno circular para la malla de elementos finitos. El enfoque desarrollado también incluye soluciones asimptóticas de las funciones de Green para grandes números de onda que resultan en una mejora de la exactitud de la metodología general. Se ha desarrollado una metodología híbrida que utiliza soluciones semi-analíticas de una cavidad en un espacio completo junto con el enfoque descrito anteriormente con el objetivo de calcular el flujo de energía de vibración radiado hacia arriba por túneles ferroviarias. Dado que esta metodología utiliza elementos finitos para modelar la estructura del túnel, su detalle de modelado es más alto que las metodologías desarrolladas anteriormente basadas en el modelado semi-analítico de la estructura del túnel. Esta metodología híbrida ha sido diseñada específicamente para el estudio de la radiación de vibración de túneles ferroviarios, la comparación entre ellos y para el estudio de la pérdida de inserción de medidas de mitigación, como suelas de baja rigidez, mantas bajo balasto o bajo losa, absorbentes de vibraciones dinámicos, etc. En esta tesis, esta metodología híbrida se utiliza para realizar una comparación del flujo de energía irradiado hacia arriba por varios tipos de túneles de ferrocarril subterráneo. Finalmente, se presenta un enfoque de modelado para el ruido re-irradiado inducido por un paso de tren dentro de los túneles ferroviarios. Este enfoque se basa en un acoplamiento débil entre el enfoque numérico integral para modelar el sistem vía/túnel/terreno descrito anteriormente y un modelo basado en método de los elementos de contorno 2.5D para la acústica interior del túnel. Usando este enfoque de modelado, se investiga y se discute la influencia de la rigidez de las fijaciones de carril en los niveles de ruido y vibración dentro de un túnel simple, así como la relación entre el ruido emitido por los carriles y la estructura del túnel

Role of Veterinarian in Rural Development of Khed Taluka of Maharashtra State

A study was carried out to determine the role of veterinarian in rural development in Khed taluka of Pune district. The survey was carried out in 19 villages of 4 subdivisions of Khed taluka by personnel interview and 210 farmers were screened. The study revealed that accessibility of veterinarian for 21.05 % (4) villages was below average, 73.68% (11) villages were average and 5.26% (1) villages were above average. The availability of veterinarian for 31.58 (6) villages was above average and rest 68.42% (13) were below average. The role in rural development of veterinarian was above average for 21.05% (4) villages, 36.84% (7) villages were average and rest 42.11% (8) villages were below average. The study also showed that 15.79% (3) villages were good, 42.12% (8) villages were average and 42.12% (8) villages were below average when total ranking of villages was done by block level veterinary service index. [Veterinary World 2008; 1(5.000): 133-135