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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.
1

Interpretação racional do ensaio DPL / Rational interpretation of DPL test

Bastos, Nélio José [UNESP] 26 February 2016 (has links)
Submitted by NELIO JOSE BASTOS null (njbastos@yahoo.com.br) on 2016-04-22T23:04:15Z No. of bitstreams: 1 Dissertação-Nélio-Jose-Bastos.pdf: 16350068 bytes, checksum: dddb1a9d279d04aa8e052ef55a31b375 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-26T19:24:39Z (GMT) No. of bitstreams: 1 bastos_nj_me_bauru.pdf: 16350068 bytes, checksum: dddb1a9d279d04aa8e052ef55a31b375 (MD5) / Made available in DSpace on 2016-04-26T19:24:39Z (GMT). No. of bitstreams: 1 bastos_nj_me_bauru.pdf: 16350068 bytes, checksum: dddb1a9d279d04aa8e052ef55a31b375 (MD5) Previous issue date: 2016-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As propriedades geomecânicas do solo são dados imprescindíveis na elaboração e execução de um projeto de engenharia geotécnica. Para isso, diversos métodos são comumente utilizados na prática tais como o ensaio à percussão (SPT) e o ensaio de cone (CPT), entre outros. Cada tipo de equipamento vai apresentar vantagens e desvantagens em função da geologia, das condições de acesso e área de montagem e trabalho. O Penetrômetro Dinâmico Leve modificado por Nilsson (2001), com medida de torque, é um equipamento leve e simples que apresenta grande mobilidade, permitindo realizar ensaios em regiões de difícil acesso, como relevo acidentado, florestas e áreas inundadas. Esse equipamento é pouco difundido no Brasil e a interpretação dos seus resultados é feita através do índice N10 que fornece uma ideia da resistência do solo, assim como o NSPT faz com o SPT. Este trabalho procurou interpretar racionalmente os resultados do DPL aplicando os mesmos conceitos de energia e propagação de onda unidimensional de tensão, hoje amplamente usados para interpretar o SPT. Foi investigada a influência da geometria de ponta no atrito mobilizado, constatando que pode-se substituir a ponteira de 90° do DPL por uma com 60° de ápice, como as usadas no CPT. É proposto uma nova formula relacionando o torque medido no DPL com o atrito lateral da ponteira, considerando as contribuições da luva cilíndrica e da ponta cônica. Ensaios de campo mostraram que esta fórmula proposta contabiliza mais adequadamente o atrito lateral, especialmente quando se usa a medida do torque residual e não a do torque máximo, além de que o peso do sistema DPL tem influência nas medidas de torques máximo e residual. Foi desenvolvida uma haste instrumentada com célula de carga e acelerômetros, com o objetivo de medir os sinais de força e aceleração durante a propagação de onda de tensão no topo da composição das hastes, através de um sistema de aquisição digital de dados. Os sinais obtidos em um ensaio de campo, realizado em conjunto com ensaios CPT, foram tratados através do próprio programa de aquisição de dados e de software desenvolvido para esta finalidade. A partir dos sinais de força e aceleração medidos foram determinadas as quantidades de energia transmitidas às hastes pela queda do martelo, determinando as perdas de energia na cravação da ponteira no solo. Verificou-se que a relação entre a energia potencial do sistema e a energia medida EFV é constante a partir de certa profundidade. Foram determinadas as forças dinâmicas mobilizadas na cravação a partir dos sinais de força e do deslocamento permanente médio da ponteira, e também através da aplicação do método CASE aos sinais de F e Zv. A partir da força dinâmica calculada, e dos atritos laterais calculados através da formula proposta, usando as medidas de torque máximo e residual, foi possível utilizar o ábaco de Robertson et al. (1986) para classificar o solo ensaiado até a profundidade de 12m, obtendo grande correspondência com os resultados apresentados na classificação através dos resultados do CPT elétrico. / Geotechnical properties of soil are given essential in the preparation and execution of a geotechnical engineering design. For this, several methods are commonly used in practice such as percussion test (SPT) and cone test (CPT), among others. Each type of equipment will have advantages and disadvantages depending on the geology, the conditions of access and mounting area and work. The Dynamic Light Penetrometer modified by Nilsson (2001), to measure torque, is a lightweight and simple tool that exhibits high mobility, allowing perform tests in areas of difficult access, such as rugged terrain, forests and wetlands. This equipment is not yet widespread in Brazil and the interpretation of results is done via the N10 index that provides an idea of the strength of the soil, as well as the NSPT makes the SPT. This study sought to rationally interpret the DPL results of applying the same concepts of energy and one-dimensional wave propagation of tension, now widely used to interpret the SPT. The influence of the tip geometry the mobilized friction was investigated, noting that one may substitute the tip 90 of the DPL by a 60 ° apex, as used in CPT. It is proposed a new formula relating the torque measured in DPL with the lateral friction of the tip, considering the contributions of the cylindrical sleeve and the conical tip. Field trials have shown that this accounts for proposed formula more suitably the lateral friction, especially when using the measurement of the residual torque, and not the maximum torque, and the weight of the DPL system has an influence on the measurements of maximum and residual torques. An instrumented with load cell rod and accelerometers, for the purpose of measuring the force and acceleration signals during stress wave propagation at the top of the stems of the composition via a digital acquisition system data has been developed. The signals obtained in a field test, carried out in conjunction with CPT trials were treated by own data acquisition software and software developed for this purpose. From the signs of strength and measured acceleration were determined amounts of energy transmitted to the rods by the hammer fall, causing energy losses in crimping the ferrule on the ground. It was found that the relationship between the potential energy of the system and the energy measure EFV is constant at a certain depth. We determined the dynamic forces mobilized in the piling from the force signals and the average displacement of the permanent ferrule, and also by applying the method to CASE signals F and Zv. From the calculated dynamic force, and the calculated lateral friction through the proposed formula, using the maximum and residual torque measurements, it was possible to use the abacus Robertson et al. (1986) tested for classifying the soil to a depth of 12m, achieving great correspondence with the results shown in sorting through the results of electric CPT.
2

Correlation of dynamic probing light (DPL) and standard penetration test (SPT) for sandy soil of alluvial origin

Perez, Waldo Flores, Cerdena, Jorge Chavez, Ramirez, Gary Duran, Montoya, Maggie Martinelli 30 September 2020 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / In geotechnical studies, the dynamic probing light (DPL) turns out to be an alternative method to the Standard Penetration test (SPT) for the determination of soil parameters. The requirement of various regulations for correlating both tests in the same field and not establishing a methodology to carry it out, limits the practical scope of dynamic probing light. Thus, this research presents a correlation methodology between the dynamic probing light (DPL) and the Standard Penetration test (SPT) specifically for sandy soils (SP and SP-SM) located in an area of Chilca, located in Cañete. - Lima Peru. For the analysis, more than 400 data pairs were used, obtaining two linear correlations between the count blow of Standard Penetration-NSPT test and the dynamic probing light method-N10, which presented an adjustment correlation between 84% and 87 %.
3

Medida de energia do DPL com instrumentação dinâmica

Figueiredo, Luiz Carlos de 02 September 2016 (has links)
Tese (doutorado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Civil e Ambiental, 2016. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2017-04-27T20:07:52Z No. of bitstreams: 1 2016_LuizCarlosdeFigueiredo.pdf: 6500104 bytes, checksum: 3e4e8d6a24a6dc8b5f300aaef47e2c43 (MD5) / Approved for entry into archive by Patrícia Nunes da Silva(patricia@bce.unb.br) on 2017-04-30T14:42:16Z (GMT) No. of bitstreams: 1 2016_LuizCarlosdeFigueiredo.pdf: 6500104 bytes, checksum: 3e4e8d6a24a6dc8b5f300aaef47e2c43 (MD5) / Made available in DSpace on 2017-04-30T14:42:16Z (GMT). No. of bitstreams: 1 2016_LuizCarlosdeFigueiredo.pdf: 6500104 bytes, checksum: 3e4e8d6a24a6dc8b5f300aaef47e2c43 (MD5) / Esta tese de doutorado aborda a medição de energia com instrumentação dinâmica para o penetrômetro leve conhecido como Dynamic Probing Light ou DPL e cujos ensaios são guiados pela International Reference Test procedure for dynamic probing (DP). Report of the ISSMFE Technical Committee on Penetration Testing of Soils – TC 16 with Reference Test Procedures - ISSMFE (1989). A região central do planalto brasileiro, apresenta extensas áreas com solos de baixa resistência à penetração dinâmica do SPT que resulta no aumento da incerteza para a estimative de carga, baseada nesse penetrômetro dinâmico. A presença no cenário da investigação geotécnica do DPL não se constitui em novidade, mas ainda não se conhece os parâmetros oriundos da medição de energia para esse penetrômetro leve. A medição da energia transferida às hastes do DPL foi feita com o uso de células de carga e acelerômetros. As células de carga foram instaladas em dois pontos: no topo e próximo do cone do DPL. Baseado na Equação da onda, foi empregado o método que considera os registros de força e velocidade no mesmo domínio do tempo, denominado EFV. A eficiência da energia do DPL foi considerada em relação à penetração permanente do cone do DPL. A medida da eficiência de energia conduziu a uma formulação da força dinâmica por penetração permanente do DPL, associada ao comprimento da haste penetrada no solo. Por fim, é apresentado um exemplo prático de aplicação da medida de energia do DPL para a engenharia com a formulação de um método para o cálculo da capacidade carga para estaca. O método tem por base a força dinâmica absorvida pelo solo, considerando o comprimento máximo de haste do DPL em 10 metros de profundidade. / This PhD thesis deals with energy measurement with dynamic instrumentation for the light penetrometer known as Dynamic Probing Light or DPL and whose tests are guided by the International Reference Test Procedure for Dynamic Probing (DP). Report of the ISSMFE Technical Committee on Penetration Testing of Soils - TC 16 with Reference Test Procedures - ISSMFE (1989). The central region of the Brazilian plateau presents extensive areas with soils of low resistance to the dynamic penetration of the SPT that results in the increase of the uncertainty for the estimative of load, based on these dynamic penetrometer. The presence in the DPL geotechnical research scenario is not new, but the parameters of energy measurement for this light penetrometer are not yet known. The energy transferred to the DPL rods was measured using load cells and accelerometers. The load cells were installed at two points: at the top and near the DPL cone. Based on the wave equation, the method that considers force and velocity records in the same time domain, called EFV, was used. The energy efficiency of the DPL was considered in relation to the permanent penetration of the DPL cone. The measurement of the energy efficiency led to a formulation of the dynamic force by permanent penetration of the DPL, associated to the length of the rod penetrated in the soil. Finally, a practical example of application of the DPL energy measure for engineering is presented with the formulation of a method for the calculation of the load capacity for cuttings. The method is based on the dynamic force absorbed by the soil, considering the maximum stem length of the DPL in 10 meters of depth.
4

IMPROVING PERFORMANCE OF MIXED-SIGNAL SIMULATION BY REDUCING THE SIMULTANEOUS EQUATION-SET

PANDEY, SANJIV 22 May 2002 (has links)
No description available.
5

Ursachen der Rissbildung bei Direktbeschichtungen mit Melaminharz-imprägnierten Papieren / Causes of cracking in direct coatings with melamine resin impregnated papers

Meder, Mark 26 November 2020 (has links)
No description available.
6

Soluciones exactas y numéricas de modelos de difusión con retardo en dominios bidimensionales y no acotados

Escolano Cerdán, Julio 16 June 2016 (has links)
No description available.
7

Métodos de diferencias finitas para la solución numérica de modelos de difusión y conducción del calor con retardo

Cabrera Sánchez, Jesús 02 June 2016 (has links)
No description available.
8

Design and implementation of an approximate full adder and its use in FIR filters

Satheesh Varma, Nikhil January 2013 (has links)
Implementation of the polyphase decomposed FIR filter structure involves two steps; the generation of the partial products and the efficient reduction of the generated partial products. The partial products are generated by a constant multiplication of the filter coefficients with the input data and the reduction of the partial products is done by building a pipelined adder tree using FAs and HAs. To improve the speed and to reduce the complexity of the reduction tree a4:2 counter is introduced into the reduction tree. The reduction tree is designed using a bit-level optimized ILP problem which has the objective function to minimize the overall cost of the hardware used. For this purpose the layout design for a 4:2 counter has been developed and the cost function has been derived by comparing the complexity of the design against a standard FA design. The layout design for a 4:2 counter is implemented in a 65nm process using static CMOS logic style and DPL style. The average power consumption drawn from a 1V power supply, for the static CMOS design was found to be 16.8μWand for the DPL style it was 12.51μW. The worst case rise or fall time for the DPL logic was 350ps and for the static CMOS logic design it was found to be 260ps. The usage of the 4:2 counter in the reduction tree infused errors into the filter response, but it helped to reduce the number of pipeline stages and also to improve the speed of the partial product reduction.
9

NUMERICAL INVESTIGATION AND PARALLEL COMPUTING FOR THERMAL TRANSPORT MECHANISM DURING NANOMACHINING

Kumar, Ravi R. 01 January 2007 (has links)
Nano-scale machining, or Nanomachining is a hybrid process in which the total thermal energy necessary to remove atoms from a work-piece surface is applied from external sources. In the current study, the total thermal energy necessary to remove atoms from a work-piece surface is applied from two sources: (1) localized energy from a laser beam focused to a micron-scale spot to preheat the work-piece, and (2) a high-precision electron-beam emitted from the tips of carbon nano-tubes to remove material via evaporation/sublimation. Macro-to-nano scale heat transfer models are discussed for understanding their capability to capture and its application to predict the transient heat transfer mechanism required for nano-machining. In this case, thermal transport mechanism during nano-scale machining involves both phonons (lattice vibrations) and electrons; it is modeled using a parabolic two-step (PTS) model, which accounts for the time lag between these energy carriers. A numerical algorithm is developed for the solution of the PTS model based on explicit and implicit finite-difference methods. Since numerical solution for simulation of nanomachining involves high computational cost in terms of wall clock time consumed, performance comparison over a wide range of numerical techniques has been done to devise an efficient numerical solution procedure. Gauss-Seidel (GS), successive over relaxation (SOR), conjugate gradient (CG), d -form Douglas-Gunn time splitting, and other methods have been used to compare the computational cost involved in these methods. Use of the Douglas-Gunn time splitting in the solution of 3D time-dependent heat transport equations appears to be optimal especially as problem size (number of spatial grid points and/or required number of time steps) becomes large. Parallel computing is implemented to further reduce the wall clock time required for the complete simulation of nanomachining process. Domain decomposition with inter-processor communication using Message Passing Interface (MPI) libraries is adapted for parallel computing. Performance tuning has been implemented for efficient parallelization by overlapping communication with computation. Numerical solution for laser source and electron-beam source with different Gaussian distribution are presented. Performance of the parallel code is tested on four distinct computer cluster architecture. Results obtained for laser source agree well with available experimental data in the literature. The results for electron-beam source are self-consistent; nevertheless, they need to be validated experimentally.
10

Correlación entre la Auscultación Dinámica Ligera (DPL) y el Ensayo de Penetración Estándar (SPT) para suelos arenosos de origen aluvial ubicados en el distrito de Chilca, provincia de Cañete – departamento de Lima. / Correlation of dynamic probing light (DPL) and standard penetration test (SPT) for sandy soil of alluvial origin located in the district of Chilca, province of Cañete, Department of Lima

Flores Perez, Waldo, Chávez Cerdeña, Jorge Augusto 13 November 2020 (has links)
En aplicaciones geotécnicas, el ensayo de penetración dinámica ligera (DPL) es un método alternativo a la Prueba de Penetración Estándar (SPT) para la determinación de los parámetros del suelo. La exigencia de diversas normativas para correlacionar ambos ensayos in situ y no establecer una metodología para realizarlo, limita el alcance práctico del DPL. La presente investigación desarrolla una metodología y una ecuación de correlación entre el ensayo de penetración dinámica ligera (DPL) y la Prueba de Penetración Estándar (SPT) específicamente para suelos arenosos (SP y SP-SM) ubicados en una zona del distrito de Chilca, provincia de Cañete, departamento de Lima. Para el análisis se utilizaron hasta 393 pares de datos, obteniendo correlaciones lineales entre el número de golpes obtenidos de la prueba de Penetración Estándar-NSPT y del ensayo de penetración dinámica ligera-N10; obteniendo un coeficiente de determinación (R2) entre 84% y 87%. La correlación obtenida se puede aplicar para obtener parámetros del suelo cuando el DPL se utiliza como complemento en investigaciones geotécnicas. / In geotechnical applications, the dynamic probing light (DPL) is an alternative method to the Standard Penetration Test (SPT) for the determination of soil parameters. The requirement of various regulations for correlating both tests in the same field and not establishing a methodology to carry it out, limits the practical scope of dynamic probing light. This research presents a correlation methodology and the correlation between the dynamic probing light (DPL) and the Standard Penetration Test (SPT) specifically for sandy soils (SP and SP-SM) located in an area of Chilca, in Cañete - Lima - Peru. For the analysis, 393 data pairs were used, obtaining two linear correlations between the blow count of Standard Penetration-NSPT test and the dynamic probing light method-N10, which presented a coefficient of determination (R2) between 84% and 87 %. This correlation can be used to obtain soil parameters when the DPL is used in complementary geotechnical investigations. / Tesis

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