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Optimization of geometric road design for autonomous vehicleAryal, Prabin January 2020 (has links)
These days most of the research related to autonomous vehicle technology focuses on vehicle technology itself and lesser on road infrastructure, including geometric design. This research project aims to lower the deficiency of research works required to make the optimized geometric road design for autonomous vehicle sustainable. In geometric design, significant concerns are designing the road geometrics such as lane width, the radius of horizontal curves, sag vertical curves and crest vertical curves, extra widening, setback distance, and intersection, making the road safer for the vehicles to travel comfortably.Road geometrics is widely designed using the stopping sight distance model, which provides sufficient time to avoid accidents and is efficient. Here in the research work, the stopping sight design model is used for autonomous vehicle technology. At first, the art of autonomous vehicle technology is studied, and a significant difference between autonomous vehicle technology and human-driven vehicle to apply stopping sight distance model is figured out. A literature study is also done for the geometric design of the road for the vehicle with the human driver and autonomous vehicle. The AASHTO model derived for the human-driven vehicle is used and modified for the autonomous vehicle, which gives the optimized geometric design for the autonomous vehicle. The Optimized geometric design parameter is designed individually in AutoCAD Civil 3D. Two road designs follow this in a random rural topography consisting of a normal road design for the vehicle with the human driver and a fully autonomous vehicle. Finally, the sustainability of optimized geometric design compared to road design for the human-driven vehicle is checked in terms of earthwork, pavement surface areas, and pavement materials volume. The result shows that the optimization of a geometric road design for autonomous vehicles is sustainable and extensive research is required.
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Evaluación del diseño geométrico de la carretera de Ferreñafe–El Liguerón km 1+100 hasta km 60+800–2022Guevara Abad, Luis Miguel January 2024 (has links)
El presente proyecto tiene como principal finalidad la evaluación del diseño geométrico de la carretera existente, de Ferreñafe al Ligueron, del KM 1 + 100 al KM 60 + 800. Según los datos obtenidos de las comisarías, la carretera mencionada ha presentado múltiples accidentes en los últimos años. Debido a esto, para verificar si cumple con los requisitos establecidos, se realizó la evaluación del diseño geométrico de la carretera en mención teniendo en cuenta el manual de carreteras DG – 2018. Por lo que, se realizó el Estudio de tráfico (IMDA) en los puntos críticos (puntos negros) que se encontraron a lo largo de toda esta carretera y se ejecutó la topografía respectiva con el apoyo de una Estación total modelo Topcon ES-105. Además, se, ver qué medidas de prevención se pueden optar para disminuir la cantidad de accidentes, garantizando la seguridad de transitabilidad del peatón y del conductor. Llegando a concluir que los principales accidentes ocasionados en esta carretera son en las zonas urbanas, debido a que no cumplen con lo que establece en el manual de carreteras DG -2018. / The main purpose of this project is to evaluate the geometric design of the existing road, from Ferreñafe to Ligueron, from KM 1 + 100 to KM 60 + 800. According to the data obtained from the police stations, the mentioned road has presented multiple accidents in the last years. Due to this, to verify if it meets the established requirements, the evaluation of the geometric design of the mentioned road was carried out taking into account the DG - 2018 road manual. Therefore, the Traffic Study (IMDA) was carried out in the critical points (black dots) that were found along this entire highway and the respective topography was carried out with the support of a Topcon ES-105 model total station. In addition, I know what prevention measures can be chosen to reduce the number of accidents, guaranteeing the safety of pedestrians and drivers. Coming to the conclusion that the main accidents caused on this road are in urban areas, because they do not comply with what is established in the DG -2018 road manual.
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Evaluación y propuesta para optimizar flujo vehicular en intersección de avenidas Chinchaysuyo con Fitzcarrald y Víctor Raúl Haya de la Torre en provincia de Chiclayo 2021Nuñez Constantino, Darwin Marino January 2024 (has links)
A lo largo de los años ha sido notorio el incremento de vehículos en el Perú, de igual manera en sus ciudades y este proyecto se desarrolla en la provincia de Chiclayo, precisamente en una intersección vial muy concurrida entre la avenida Chinchaysuyo con avenida Fitzcarrald y la avenida Víctor Raúl Haya de la Torre. En dicha intersección se genera congestión vehicular, esto se puede evidenciar en las colas de vehículos y la excesiva demora que se generan paracruzar una avenida sobre todo en horas punta. Teniendo en cuenta esta problemática y enfocando a la Ingeniería de Tránsito, la cual busca una planificación, diseño y principalmente busca una solución para mejorar el flujo vehicular. La investigación se centrará en analizar dicha intersección, elaborar un estudio de tráfico, levantamiento topográfico, con estos estudios se elabora un nuevo diseño geométrico, con esto también se hace una simulación vehicular. Al resultado de todos los datos se evaluarán dos propuestas y se determinara cual es la más
conveniente para dicha intersección y se elaborara un modelamiento elaborando el programa de simulación Synchro 8. / Throughout the years, the increase in vehicles has been notorious in Peru, in the same way in its cities and this project is developed in the province of Chiclayo, precisely in a very busy road intersection between Chinchaysuyo avenue with Fitzcarrald avenue and Víctor Raul avenue. Haya de la Torre. In this intersection, traffic congestion is generated, this can be evidenced in the queues of vehicles and the excessive delay that is generated to cross an avenue, especially at peak times. Taking into account this problem and focusing on Traffic Engineering, which seeks planning, design and mainly seeks a solution to improve traffic flow. The research will focus on analyzing said intersection, developing a traffic study, topographic survey, with these studies a new geometric design is developed, with this a vehicular simulation is also made.
At the result of all the data, two proposals will be evaluated and it will be determined which is the most convenient for said intersection and a modeling will be elaborated using the Synchro 8 simulation program.
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Road Infrastructure Readiness for Autonomous VehiclesTariq Usman Saeed (6992318) 15 August 2019 (has links)
Contemporary research
indicates that the era of autonomous vehicles (AVs) is not only inevitable but
may be reached sooner than expected; however, not enough research has been done
to address road infrastructure readiness for supporting AV operations. Highway
agencies at all levels of governments seek to identify the needed
infrastructure changes to facilitate the successful integration of AVs into the
existing roadway system. Given multiple sources of uncertainty particularly the
market penetration of AVs, agencies find it difficult to justify the
substantial investments needed to make these infrastructure changes using
traditional value engineering approaches. It is needed to account for these
uncertainties by doing a phased retrofitting of road infrastructure to keep up
with the AV market penetration. This way, the agency can expand, defer, or
scale back the investments at a future time. This dissertation develops a real
options analysis (ROA) framework to address these issues while capturing the
monetary value of investment timing flexibility. Using key stakeholder feedback,
an extensive literature review, and discussions with experts, the needed
AV-motivated changes in road infrastructure were identified across two stages
of AV operations; the transition phase and the fully-autonomous phase. For a
project-level case study of a 66-mile stretch of Indiana’s four-six lane
Interstate corridor, two potential scenarios of infrastructure retrofitting
were established and evaluated using the net present value (NPV) and ROA
approaches. The results show that the NPV approach can lead to decisions at the
start of the evaluation period but does not address the uncertainty associated
with AV market penetration. In contrast, ROA was found to address uncertainty
by incorporating investment timing flexibility and capturing its monetary
value. Using the dissertation’s framework, agencies can identify and analyze a
wide range of possible scenarios of AV-oriented infrastructure retrofitting to
enhance readiness, at both the project and network levels.
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Parâmetros do projeto geométrico para trens de passageiros de alta velocidade e longo percurso. / Geometric design parameters of passenger trains for high speed and long journey.Stech, Pedro Henrique 13 December 2011 (has links)
Este trabalho tem como objetivo principal direcionar a tomada de decisões para a escolha dos diferentes parâmetros que envolvem o alinhamento horizontal e vertical do projeto geométrico ferroviário de trens de alta velocidade (TAV) e de longo percurso, bem como descrever conceitos teóricos para parâmetros de segurança e conforto, baseados em normas internacionais. A pesquisa se desenvolve através de consultas em revistas especializadas, artigos, publicações, normas técnicas e livros. Pela escassez de dados em língua nacional e material bibliográfico desatualizado, as pesquisas se concentram essencialmente em material internacional. Apesar do Brasil ser um dos países em desenvolvimento com maior ascensão no cenário global, tem apresentado, nas últimas décadas, sérios problemas de infra-estrutura devido a uma distribuição desequilibrada na área de transportes, com altíssima concentração no modo rodoviário, com aeroportos e rodovias operando acima da capacidade satisfatória, além de um leque limitado de alternativas de transporte. Devido à falta de investimentos no setor ferroviário, grande parte da malha ferroviária brasileira tornou-se inoperante ou até mesmo inexistente, resultando numa enorme diminuição da mão de obra qualificada e formação acadêmica nesse ramo. Como conseqüência, os estudos relacionados ao projeto ferroviário também foram afetados diretamente. Nesse contexto, é importante que se resgate normas, publicações, especificações técnicas e experiências adotadas em outros países com sólidas tradições ferroviárias, de modo a incorporar em nossa formação acadêmica tais conceitos, como é um dos objetivos dessa dissertação. / This dissertation has as main objective to guide in taking decisions for the selection of different parameters which involve the horizontal and vertical railway geometric design of high speed (HST) and long distance trains as well as theoretical concepts for describing security parameters and comfort, based on international standards. The research is developed through consultations in specialized magazines, articles, publications, standards and technical books. Due to the scarcity of data in the national language and outdated library materials, the research focuses primarily on international material. Although Brazil is a developing country with one of the highest rises in the global scene, the country has faced in recent decades serious infrastructure problems due to an uneven distribution in the area of transport, with high concentration in the road, and airports and roads operating above satisfactory capacity, resulted by a limited range of transportation alternatives. Due to the lack of investment in the railway sector, much of the Brazilian railway system became inoperative or even nonexistent, resulting in a tremendous decrease of skilled labor and academic training in this field. As a result, studies related to the railway project have also been directly impacted. In this context, it is important to rescue standards, publications, experiences and technical specifications adopted in other countries with strong tradition in railways in order to incorporate these concepts into our academic formation, which is one of the purposes of this dissertation.
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Análisis de sistemas radiantes sobre geometrías arbitrarias definidas por superficies paramétricasSaiz Ipiña, Juan Antonio 01 December 1995 (has links)
En esta tesis se presenta un método para analizar antenas montadas sobre estructuras arbitrarias. La Optica Geométrica (GO) y la Teoría Uniforme de la difraccion (UTD), han sidoempleadas para analizar los efectos que la estructura produce sobre el diagrama de radiación de la antena emisora. Para la descripción geométrica de la estructura, han sido utilizados parches NURBS (Non Uniform Rational B-Spline), por lo que el método presentado, es compatible con la mayoría de los programas gráficos disponibles en el mercado.EL tratamiento de geometrías arbitrarias requiere un código eficiente en el análisis de tres dimensiones.Por otro lado, para obtener resultados satisfactorios, la descripción de la superficie de la estructura, debe ser muy próxima al modelo real, sin embargo, esto complica el tratamiento computacional. Aquí la estructura es modelada mediante un conjunto de parches NURBS, que unidos entre sí, describen el modelo completo. Esta descripción permite manipular superficies arbitrarias con un bajo numero de parches, lo que significa un volumen de información reducido.La descripción inicial por NURBS del modelo, es acompañada con información complemetaria como por ejemplo: la tipología de las superficies, las curvas frontera, el tipo de material, etc. Esto es imprescindible para la aplicación de criterios de selección dedicados a la aceleración del proceso.El método tras leer la descripción del modelo, descompone los parches NURBS en superficies racionales de Bezier. Un parche de Bezier es también una superficie paramétrica definida en términos de una combinación lineal de los polinomios de Bernstein.Las antenas son modeladas usando modelos numéricos simples basados en agrupaciones de dipolos infinitesimales eléctricos y magnéticos. Esta caracterización de la antena es muyventajosa ya que con un numero reducido de datos de entrada, la fuente queda definida para cualquier dirección del espacio y el valor del campo radiado puede ser calculado fácilmente.El análisis electromagnético de los efectos que contribuyen al campo dispersado por la geometría comienza con una selección rigurosa de la geometría iluminada desde la fuente.Unicamente los parches de Bezier iluminados serán almacenados por el ordenador durante el análisis. La filosofía de este proceso es descartar aquella parte de la geometría que no contribuye a los efectos de dispersión.El campo total calculado es la superposición de los siguientes efectos pertenecientes a la GO y a la UTD: campo directo procedente de la fuente, campo reflejado por los parches de Bezier, campo difractado por las aristas del modelo definidas como curvas de Bezier, ondas de superficie, dobles reflexiones, reflexione-difraccion y difraccion-reflexión. El método ha sido diseñado para analizar campo cercano y lejano. El mayor gasto computacional se debe a la búsqueda de los puntos de dispersión, por lo que antes de emplear los algoritmos de intersección es necesario aplicar un conjunto de criterios rápidos dependientes de la dirección de observación.El principio de Fermat en combinación con el Gradiente Conjugado (CGM) es usado para obtener de manera eficiente los puntos de dispersión sobre la estructura. Para cada efecto, laposible ocultación de la trayectoria completa del rayo es examinada, por ello, si el rayo corta alguno de los parches de Bezier su contribución será descartada. Los dobles efectos son tratados como una generalización de los simples efectos.El método desarrollado es eficiente ya que precisa de un numero reducido de superficies para modelar objetos complejos lo que se traduce en bajos requerimientos de memoria y reducidos tiempos de calculo. / In this thesis a method to analyze antennas on board of complex bodies is presented. The Geometrical Optics (GO) and Uniform Theory of Diffraction (UTD) have been used to analyze the effect of the structure in the radiation pattern of the antennas. The bodies are geometrically modelled by using NURBS (Non Uniform Rational B-Spline) surfaces. In addition to be accurate and efficient, the method is compatible with most of the modern CAGD (Computer Aided Geometric Design) available programs.The treatment of arbitrary geometries requires a code which can carry out an efficient 3D analysis. To obtain accurate results the description of the surface must be close to the real model, however this complicates the computational procedure. Here the structure is modeled by a collection of individual N.U.R.B.S. surface patches joined to form a complete description of the surface model. The NURBS description is able to manipulate free form surfaces with a low number of patches, and therefore, with a low amount of information. The initial description of the model by NURBS surfaces is accompanied with other complementary data for example : the topology of the surfaces, the boundary curves, the types of material and other inputs. It is very interesting to apply criteria to make the complete analysis faster.The method reads the NURBS description of the model and transforms the NURBS into the rational BEZIER surfaces. A rational BEZIER patch is also a parametric surface defined in terms of a linear combination of Bernstein polynomials.The antennas are modelled using simple numerical models based on arrays of electric and magnetic infinitesimal dipoles. This antenna modelization is very advantageous because with a little input data, the source is defined in any direction and the field value is readily accessible.The electromagnetic analysis of the contributive effects to the scattering field by the geometry, starts with the rigorous selection of the geometry illuminated from the source. Only the Bezier patches illuminated will be in memory of the computer during the analysis. The philosophy of this previous process is to discard in the process the part of the geometry which does not contribute to the scattering effects.The total field is the superposition of the following GO and UTD field components: direct field from the source, reflected fields from the Bezier patches of the model, diffracted fields from the arbitrary edges defined as a Bezier curves, creeping waves, double reflected field and diffracted-reflected and reflected-diffracted fields. The search of specular and diffraction points are the most CPU time consuming, thus before using the intersection algorithms it is necessary to apply a set of fast selection criteria which depend on the observation direction.The Fermat principle in conjunction with the Conjugate Gradient Method (CGM) is used for obtaining efficiently the reflection points and diffraction points on the structure. For each effect the complete ray path is examined to see whether or not it is interrupted by any Bezier patch of the model, in this case the field component is not computed. The double effects are treated using a generalization of the single effects algorithms. The method has been developed to analyze the near and far field cases for different frequencies.The developed method is quite efficient because it makes use of a small number of surfaces to model complex bodies, so it requires few memory and low computing time.
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交通運用状態を考慮した道路計画設計のための交通容量とサービス水準に関する研究中村, 英樹, 大口, 敬, 森田, 綽之 03 1900 (has links)
科学研究費補助金 研究種目:基盤研究(B) 課題番号:17360245 研究代表者:中村 英樹 研究期間:2005-2007年度
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Parâmetros do projeto geométrico para trens de passageiros de alta velocidade e longo percurso. / Geometric design parameters of passenger trains for high speed and long journey.Pedro Henrique Stech 13 December 2011 (has links)
Este trabalho tem como objetivo principal direcionar a tomada de decisões para a escolha dos diferentes parâmetros que envolvem o alinhamento horizontal e vertical do projeto geométrico ferroviário de trens de alta velocidade (TAV) e de longo percurso, bem como descrever conceitos teóricos para parâmetros de segurança e conforto, baseados em normas internacionais. A pesquisa se desenvolve através de consultas em revistas especializadas, artigos, publicações, normas técnicas e livros. Pela escassez de dados em língua nacional e material bibliográfico desatualizado, as pesquisas se concentram essencialmente em material internacional. Apesar do Brasil ser um dos países em desenvolvimento com maior ascensão no cenário global, tem apresentado, nas últimas décadas, sérios problemas de infra-estrutura devido a uma distribuição desequilibrada na área de transportes, com altíssima concentração no modo rodoviário, com aeroportos e rodovias operando acima da capacidade satisfatória, além de um leque limitado de alternativas de transporte. Devido à falta de investimentos no setor ferroviário, grande parte da malha ferroviária brasileira tornou-se inoperante ou até mesmo inexistente, resultando numa enorme diminuição da mão de obra qualificada e formação acadêmica nesse ramo. Como conseqüência, os estudos relacionados ao projeto ferroviário também foram afetados diretamente. Nesse contexto, é importante que se resgate normas, publicações, especificações técnicas e experiências adotadas em outros países com sólidas tradições ferroviárias, de modo a incorporar em nossa formação acadêmica tais conceitos, como é um dos objetivos dessa dissertação. / This dissertation has as main objective to guide in taking decisions for the selection of different parameters which involve the horizontal and vertical railway geometric design of high speed (HST) and long distance trains as well as theoretical concepts for describing security parameters and comfort, based on international standards. The research is developed through consultations in specialized magazines, articles, publications, standards and technical books. Due to the scarcity of data in the national language and outdated library materials, the research focuses primarily on international material. Although Brazil is a developing country with one of the highest rises in the global scene, the country has faced in recent decades serious infrastructure problems due to an uneven distribution in the area of transport, with high concentration in the road, and airports and roads operating above satisfactory capacity, resulted by a limited range of transportation alternatives. Due to the lack of investment in the railway sector, much of the Brazilian railway system became inoperative or even nonexistent, resulting in a tremendous decrease of skilled labor and academic training in this field. As a result, studies related to the railway project have also been directly impacted. In this context, it is important to rescue standards, publications, experiences and technical specifications adopted in other countries with strong tradition in railways in order to incorporate these concepts into our academic formation, which is one of the purposes of this dissertation.
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Roštový kotel na spalování biomasy / Grate Boiler for Biomass CombustionSzabó, Gergely January 2016 (has links)
The thesis deals with the design of a grate steam boiler which has natural circulation and is determined for combustion of wood chips. The boiler has a capacity of 45 t/h and produces superheated steam with the output parameters of 3,5 MPa and 450 °C at the 125 °C feed water temperature. Stoichiometric calculations and the flue gases enthalpy calculations are based on the composition of the specified fuel. The efficiency and fuel consumption of the boiler is also determined. The thesis mainly focuses on the thermal calculation and geometric design of the individual heat transfer surfaces of the boiler. The drawing documentation of the steam boiler is available in the attachment of the thesis.
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Optimal geometric configuration of a cross bore in thick compound cylindersKiplagat, N. 09 1900 (has links)
M. Tech. (Department of Mechanical Engineering, Faculty of Engineering and Technology), Vaal University of Technology. / The purpose of this research was to develop optimal numerical solutions that can be employed during the design of cross bored thick-walled compound cylinders. The geometric design parameters of a cross bored compound cylinder that were optimized include shrinkage pressure, cross bore size, shape, location, and obliquity.
Finite Element Analysis (FEA) modeling software called Abaqus version 2019 was used to
generate numerical solutions. A total of 48 different part models were created and analyzed in this work. The generated FEA results from these models were validated using analytical
solutions developed from Lame’s theory. The effects of shrinkage pressure on hoop stresses and Stress Concentration Factor (SCF) were studied to determine the optimal conditions. The optimum shrinkage pressure obtained was henceforth used for further analysis in this work. In addition, using one factor at time optimization technique, an optimization process was carried out to determine the optimal combination of the cross bore configuration geometry that gives minimum SCF. These parameters of cross bore configuration geometry include different sizes of either circular or elliptical-shaped cross bore, positioned at radial, offset, and/or inclined. The analyses of the effects of shrinkage pressure ranging from 4.4733 to 223.662 MPa on 11 different part models, established that the shrinkage pressure of 89.464 MPa generated the minimum SCF magnitude of 3.02.
After analyzing 8 different circular cross bore size ratios ranging from 0.1 to 0.8, at the radial position, it was established that the hoop stress increases with an increase in a cross bore size. The smallest cross bore size ratio of 0.1 gave the lowest hoop stress and minimum SCF of 3.02. Whereas the highest stress was developed at the cross-size ratio of 0.8 with an SCF magnitude of 6.75. The minimum magnitude of SCF translates to a reduction of the pressure carrying capacity of the compound cylinder by 67% than a similar plain compound cylinder. Generally, offsetting of the circularly shaped cross bore from the radial position, led to a reduction of the magnitude of SCFs. For instance, from the 8 offset positions analyzed, the minimum SCF occurred at the offset position of 0.006 m with a magnitude of 2.50. This SCF magnitude indicated a reduction of pressure carrying capacity of 60% in comparison to a similar plain compound cylinder.
Evaluation of 12 different diameter ratios of elliptical-shaped cross bore ranging from 0.5 to
10, at the radial position, established the lowest SCF magnitude of 1.33 that occurred at a
diameter ratio of 5. Henceforth, this optimum diameter ratio was used for further analysis. This aforesaid SCF magnitude translated to a reduction of the pressure carrying capacity of the compound cylinder by 24.81% when compared to a similar plain compound cylinder. Besides, offsetting of elliptically shaped cross bore generally decreased the magnitudes of SCFs. Therefore, for elliptically shaped cross bore, the lowest SCF occurred at radial position with magnitude of 1.33. A general comparison between the effects of circular and elliptical cross bore, established that the elliptical-shaped cross bores generated both lower hoop stresses and SCFs than those of circularly shaped cross bores. On the other hand, oblique elliptical offset cross bores along the Z-axis of the compound cylinder led to an increase in SCFs. As the oblique angle increased from 0 0 to 75 0, the SCFs also increased progressively, however, there was a significant increase in SCF when the inclination angle increased from 60 0 to 75 0. The lowest and highest SCF magnitude was 1.52 and 1.92 at 15 0 and 6.19 at 75 0, respectively.
Overall, the optimum geometric configuration of a cross bore in a thick compound cylinder
was found to be elliptically shaped, offset at radial position which is an obliquity angle of 0 0
having a diameter ratio a/b of 5.
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