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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

Plan de Negocio para la Comercialización de Nueva Línea de Repuestos Alternativos ALOR para equipos de construcción

Cabrera Arias, Nícolas Joel, Almonacin Garcia, Victor Wilfredo, Aguirre Alvarado, Jhon Cristian 19 September 2019 (has links)
El presente trabajo de investigación desenvuelve una propuesta de comercialización de repuestos alternativos para maquinaria de construcción con características diferenciadas en términos de diseño y fabricación del producto dentro del segmento del mercado alternativo; brindando piezas mecánicas de encaje perfecto para maquinaria, esto se traduce sustancialmente en la mejora del rendimiento de la maquinaria. En el ambiente de las medianas y pequeñas constructoras, los repuestos alternativos son requeridos cuando el equipo mecánico ha llegado a alcanzar las horas de trabajo dentro de la garantía original; y a partir de este punto en el tiempo de vida de la maquinaria se comienzan a analizar “eficiencia en costos”, originándose la posibilidad del uso del alternativo frente al original y para ello cobra importancia, accesibilidad, la inmediatez, la disponibilidad y precio del repuesto. El segmento de clientes objetivo se caracteriza por dueños de equipo de construcción del líder mundial en maquinaria pesada que operan en proyectos de pequeña o mediana envergadura, quienes hoy se encuentran tomando decisiones a corto plazo sobre la manera de cómo mantener sus equipos, ellos no buscan una reconstrucción completa de sus equipos con partes premium, ellos encuentran mayor valor en la prontitud de arreglar el equipo para volver a trabajar, estas decisiones a menudo están íntimamente relacionadas con presiones internas para atender el flujo de caja y metas mensuales de su negocio. Este segmento de clientes adquiere actualmente repuestos alternativos experimentando insatisfacción por la baja calidad de los productos existentes en el mercado peruano. Para este segmento, la propuesta ofrece el mayor rendimiento que se puede brindar al “Equipo Clásico” empleando piezas de encaje perfecto de gran fiabilidad y confiabilidad con una disponibilidad garantizada a través de una red de distribuidores que serán ubicados a nivel nacional y todo a un costo razonable por los repuestos alternativos. El mercado potencial está compuesto por todos los clientes que poseen equipos de la marca líder en maquinaria pesada clásico (antigüedad mayor a 10 años), que para un parque más de 1,500 equipos representan un potencial de mercado estimado mayor a 7 MM USD; de otro lado el mercado meta está compuesto por el 30% de los clientes del mercado potencial que se alcanzará el 3er año con una oportunidad estimada mayor a los 2MM USD. Los proveedores que operan en el mercado actual de partes y repuestos alternativos se encuentran atomizados y dispersos, en este contexto no existe una marca líder del segmento; esto representa una clara oportunidad para la compañía líder nacional en maquinaria pesada puesto que además del producto ofrecido, puede usar el respaldo que lo caracteriza para conseguir penetrar y posicionarse en el segmento a través del lanzamiento de repuestos ALOR. La inversión para puesta en marcha del negocio es de 800,000 USD, siendo que el financiamiento en deuda corresponde al 62.5%, el destino de las inversiones será en activo tangible relacionadas principalmente con la locación y preparación de las tiendas en los principales conglomerados de repuestos del país y el nivel de stock inicial. Se ha logrado demostrar que el negocio es rentable analizando sus principales indicadores y ello conlleva a que es perfectamente factible continuar con el proceso de expansión del negocio abriendo nuevos puntos de venta en el país; sin embargo; este análisis no forma parte del alcance del desarrollo del presente trabajo de investigación. Es así que para un escenario moderado de proyecciones del flujo de caja del negocio que considera una inflación del 2.5% y un crecimiento del 20% anual de las ventas; tenemos un periodo de retorno de la inversión de 5 años. En la evaluación financiera realizada, obtenemos un Valor Actual Neto de $ 576,184.00, además de una Taza Interna de Retorno del 18% que sobrepasa la tasa de descuento utilizad; lo que nos demuestra que el emprendimiento resulta rentable al superar los ingresos a sus egresos durante los siguientes 5 años futuros. / This research paper develops a proposal for the commercialization of alternative spare parts for heavy construction machinery with the characteristics of differentiation in terms of product design and manufacturing within the segment of the alternative market; providing perfect fit mechanical parts for machinery, this translates substantially into improving the performance of the machinery. In medium and small construction companies, alternative spare parts are required when machinery has reached the working hours within the original warranty; and from this point in the lifetime of the machinery medium and small construction companies begin to analyze "cost efficiency", leading the possibility of using the alternative spare parts against the genuine and for this it becomes important, accessibility, immediacy, availability and price of spare parts. The target customer segment is characterized by construction machinery owners of the world leader in heavy machinery operating on small or medium-sized projects, who are today making short-term decisions on how to keep their machinery, they don't seek a complete overhaul of their machinery with premium parts, they find greater value in the promptness of fixing the machinery to get back to work, these decisions are often closely related to pressures to meet cash flow and monthly business goals. This segment of customers currently acquires alternative spare parts experiencing dissatisfaction with the low quality of existing products in the Peruvian market. For this segment, the proposal offers the highest performance that can be provided to the "Classic Machinery" using perfect fit spare parts of great reliability with guaranteed availability through a network of distributors that will be located nationwide and all of this at a reasonable cost for alternative spare parts. The potential market is made up of all customers who own machinery from the leading brand in classic heavy machinery (older than 10 years), which for a park of more than1,500 equipment represents an estimated market potential greater than USD 7 MM; on the other hand the target market is made up of 30% of the potential market customers who will reach the 3rd year with an estimated opportunity greater than 2MM USD. The suppliers that operate in the current market of alternative spare parts are atomized and dispersed, in this context there is no leading brand in the segment; this represents a good opportunity for the national leader in heavy machinery company since in addition of the product offered, it can use the support that characterizes it to get penetrated and positions in the segment through the launch of ALOR spare parts. The investment for start-up of the business is 800,000 USD, with debt financing being 62.5%, the destination of the investments will be tangible assets related mainly to the location and preparation of the stores in the main conglomerates of country spare parts and initial stock level. It has been possible to demonstrate that the business is profitable by analyzing its main indicators and this means that it is perfectly feasible to continue the process of expanding the business by opening new points of sale in the country; however; this analysis is not part of the scope of the development of this research paper. Thus, for a moderate scenario of business cash flow projections that considers inflation of 2.5% and 20% annual sales growth; we have a 5-year return on investment period. In the financial evaluation, we obtain a Net Present Value of $576,184.00, which shows us that entrepreneurship is profitable by surpassing the income to its egress for the next 5 years. In addition, an Internal Rate of Return of 18% that exceeds the discount rate used. / Trabajo de investigación
2

Análisis de los métodos de eliminación de material para construcción de sótanos en Proyectos que presentan suelo granular en Lima Metropolitana / Analysis of material removal methods for basement construction in projects that present granular soil in Metropolitan Lima

Guio Sivipaucar, Juan Diego, Cayllahua Huaman, Dennis Alfredo 25 September 2019 (has links)
La presente tesis pretende analizar la importancia que tienen las metodologías de excavación en los edificios de la ciudad de Lima Metropolitana. Las metodologías más usadas son: conformación de rampas, conformación de banquetas, método del pasamanos con el uso de banquetas, método de cuchara a cuchara, uso de faja transportadora, uso de baldes basculantes y el sistema de izaje vertical. En el país no se tiene conocimiento del tipo de método o control que se debe regir para un eficiente proceso de eliminación de material para la construcción de sótanos, dando así confianza a las empresas subcontratas que se encargan de la ejecución de esta etapa de movimiento de tierras o también experiencia del staff de producción. El buen control y el manejo de una buena producción de eliminación de material ayudarían a determinar la eficiencia de un proceso a futuro, lo que nos permite la buena elección de una metodología de mayor eficiencia, con la finalidad de evitar un mal flujo de producción. Para este estudio se analizará 4 edificios ubicados en los distritos de Lima Metropolitana. Donde este análisis se limitará a proyectos que presenten áreas entre 700 – 1200 m2, contengan la construcción de 4 a más sótanos, que se encuentren ubicadas en zonas características al suelo de Lima que son los suelos Granulares tipo gravas y que presenten las condiciones óptimas en cuanto a maquinaria para el desarrollo de las excavaciones profundas. La importancia de este trabajo es asegurar la mejora de los procesos y métodos en excavaciones profundas de edificaciones con ciertas características constructivas en base al estudio del proceso constructivo de excavaciones para la construcción de sótanos mediante ratios, lo que nos permitirá determinar la eficiencia por anillo y por proyecto de este proceso durante la eliminación de material. / The following thesis aims to analyze the importance of excavation methodologies in the buildings of the city of Metropolitan Lima. The most used methodologies are: ramp installation, sidewalk installation, handrail method using sidewalks, spoon to spoon method, conveyor belt usage, use of tilting buckets, and vertical lifting system. In the country, there is no knowledge of the method or control that should be used for an efficient process of material removal for basement constructions; hence, there is trust in subcontracting companies which are responsible or perform for this activity based on experiences already carried out in other similar projects. The purpose of this thesis project is to develop the appropriate control and management of a good production of material removal that would help to establish the efficiency of any process in the future. This study will analyze 4 buildings located in the districts of Metropolitan Lima. This analysis will be limited to projects which areas are ranked between 700 - 1200 m2, include the construction of 4 or more basements, with locations based in typical areas that represent the main characteristics of the Lima soil. Within the group of soils, there is focus in the granular gravel type that shows the optimal conditions in terms of suitable machinery for deep excavations performance. The importance of this work is to ensure the improvement of processes and methods in deep excavations of buildings that present some construction characteristics, based on the study of the construction process of basement excavations by ratios, which will allow to determine the efficiency by ring and by project of this process during the material removal phase. / Tesis
3

Koncept nízkopodlažního přepravníku stavebních strojů / Concept of a low loader trailer for the construction machinery

Benda, Petr January 2019 (has links)
This diploma thesis deals with a concept and strength analysis of a low loader trailer for construction machinery. The thesis was created in cooperation with company ZDT Nové Veselí. The first part presents an overview of ways how to transport construction machinery and fundamental legal requirements for these devices. The main part of the thesis contains description of the trailer and its simplified model intended for the strength analysis. The last section presents an evaluation of results that had been achieved and at the very end the thesis contains partial drawing documentation.
4

Control of a Hydraulic Hybrid System for Wheel Loaders

Reichenwallner, Christopher, Wasborg, Daniel January 2019 (has links)
In recent years many companies have investigated the use of hybrid technology due to the potential of increasing the driveline’s efficiency and thus reducing fuel consumption. Previous studies show that hydraulic hybrid technology can be favourable to use in construction machinery such as wheel loaders, which often operate in repetitive drive cycles and have high transient power demands. Parallel as well as Series hybrid configurations are both found suitable for wheel loader applications as the hybrid configurations can decrease the dependency on the torque converter. This project has investigated a novel hydraulic hybrid concept which utilizes the wheel loaders auxiliary pump as a supplement to enable both Series and Parallel hybrid operation. Impact of accumulator sizes has also been investigated, for which smaller accumulator sizes resembles a hydrostatic transmission. The hybrid concept has been evaluated by developing a wheel loader simulation model and a control system based on a rule-based energy management strategy. Simulation results indicate improved energy efficiency of up to 18.80 % for the Combined hybrid. Moreover, the accumulator sizes prove to have less impact on the energy efficiency. A hybrid system with decreased accumulator sizes shows improved energy efficiency of up to 16.40 %.
5

Implementação de método de potência sonora em serra-mármore / Implementing a sound power method for testing noise on masonry saw

Barbosa, Adriano Aurelio Ribeiro, 1977- 25 August 2018 (has links)
Orientador: Stelamaris Rolla Bertoli / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-25T10:59:34Z (GMT). No. of bitstreams: 1 Barbosa_AdrianoAurelioRibeiro_D.pdf: 5486627 bytes, checksum: fd9ac7f13185126d6aabd57ae00f989b (MD5) Previous issue date: 2014 / Resumo: A poluição sonora e sua influência sobre o meio ambiente e a qualidade de vida das pessoas têm sido focos de várias pesquisas em diversas partes do mundo. Estudos apontam a construção civil como fator gerador de ruídos que incomodam a sociedade. A contribuição das máquinas e das ferramentas utilizadas nas obras tem influência direta neste processo. Os usos frequentes destes facilitadores estão entre as vertentes de melhoria de qualidade, racionalização dos processos e aplicação de inovações tecnológicas no setor. O estudo do comportamento e a caracterização dos ruídos ambientais nos canteiros de obras da construção civil, devido às operações com equipamentos elétricos, apresentam importância para o setor. A determinação do ruído gerado por máquinas, quando em contato com as superfícies de corte dos materiais de construção, contribui com as ações de controle do ruído em atividades desta natureza para fins ocupacionais e de conforto ambiental. A serra-mármore é uma máquina elétrica manual, portátil, largamente utilizada, na construção civil, para executar pequenos cortes e acabamentos em pisos, azulejos, telhas, tijolos e madeiras e destaca-se pela sua versatilidade, praticidade, leveza e ergonomia. O objetivo deste trabalho é propor um material de condição de carga padrão para implementação de método de determinação de potência sonora do ruído gerado por serra-mármore e estabelecer a incerteza de medição associada às operações. A metodologia utilizada para o estudo considerou os níveis de ruído gerados nas operações de corte em relação ao ruído do equipamento sem carga em concordância com a ISO 3744:2010, que especifica a determinação de níveis de potência sonora de ruído transmitido através do ar, por um método de engenharia, num campo livre sobre um plano refletor. Os resultados indicaram elevados níveis de ruído com a carga padrão proposta e diferentes materiais de construção em relação às atividades da serra-mármore sem carga. Os níveis globais de potência sonora obtidos nas operações chegaram a 110,1dB. A relação da condição do equipamento vazio e com carga apontam diferenças de até 10,0dB. Os resultados revelaram similaridade nas incertezas de medição nas operações de serra em diferentes condições de carga. Foi possível avaliar quantitativamente o nível de ruído gerado nas operações de corte, bem como propor um material de carga padrão para a determinação de níveis de potência sonora. Resultou em 4,3dB a incerteza de medição expandida nas operações da serra-mármore em campo aberto sobre um plano refletor. O estudo representa ainda uma contribuição na análise de ruído nas obras, considerando as dificuldades na obtenção de valores dos espectros sonoros nas operações de máquinas portáteis de construção civil na literatura, como a serra-mármore / Abstract: Worldwide, noise pollution and its influence on environment and quality of life have been studied. And so, such researches have pointed out the building construction as the main responsible for disturbing sounds today. In this sector, machinery and tools have direct influence on this process. Thus, the regular use of such tools are the main concern aiming quality improvement, streamlining processes and application of technological innovations in the industry. For this reason, the study and characterization of environmental noise behavior at construction sites (due to electrical equipment) is relevant for the sector, in order to contribute to noise control actions in construction activities aiming occupational purposes and environmental comfort. The masonry saw (circular saw for granite stone) is an electrical device, regularly used on building construction for cutting and shaping floors, tiles, bricks and woods and stands out for its versatility, practicality, lightness and ergonomics. Thus, the aim of our study is to design material of proper standard condition and measurement uncertainty associated with operations and measurements to implement the method for determining sound power of noise generated by masonry saw. The method applied in this study was comparing noise levels - generated by cutting operations - and the noise of the equipment without charge, according the ISO 3744:2010 (which specifies sound levels transmitted through the air, by a method of engineering, in a free field over a reflecting plane. Results have indicated high levels of noise with the proposed standard charge and different building materials in relation to the activities of the unloaded masonry saw. The overall sound power levels obtained from operations reached 110.1 dB. The ratio of unloaded and loaded device points to differences of up to 10.0 dB. Also, results have revealed a similarity in the measurement uncertainties in masonry saw operations on different load conditions. It was possible to quantitatively assess the noise level generated during cutting operations, so proposing a standard charge for determining sound power levels. Finally, the expanded measurement uncertainty has resulted in 4.3 dB of the masonry saw in an open field over a reflecting plane. Moreover, the study represents a great contribution for analyzing noise levels from the use of portable machinery on building construction, considering the difficulties in obtaining values of sound spectra in the literature / Doutorado / Arquitetura e Construção / Doutor em Engenharia Civil
6

Vliv ceny pohonných hmot na cenu stavby / The influence of fuel prices to the cost of building

Kaplan, Ondřej January 2016 (has links)
In theoretical part of the thesis I first mentioned a project management structures and the way it compiles the price of the works. I also noted a general procedure for calculating the price of work construction machinery. Conclusion theoretical part I dedicated the composition, development and consumption of fuel prices. The aim of this thesis was to analyze the effect of changes in fuel prices on the cost of the building and generalize this affect the whole construction output. This target has been demonstrated in practical part of this work. I was doing calculations on a particular project.
7

Beanspruchungsminimierung keramischer Gleitlager mit Hilfe der FEM

Stentzel, Christian 05 July 2019 (has links)
Zur Realisierung des neuartigen und keramischen Gleitlagers unter den Einsatzbedingungen hoher und stoßartiger Belastungen wird auf die Finite-Elemente-Methode (FEM) zurückgegriffen, um ein keramikgerechtes Design abzuleiten. Unter Einbeziehung der umgebenden Strukturen, wie der Einbettung und dem Bolzen, werden mit Hilfe der FEM konstruktive und werkstoffliche Parameterstudien durchgeführt. Als Basis der Untersuchungen dienen typische Arm- und Koppelstangenverbindungen aus dem Bereich der mobilen Arbeitsmaschinen. Oberstes Ziel der Studien ist die Minimierung der Zugbeanspruchungen im keramischen Werkstoff unter Last nach dem Kriterium des „Spannungsminimums“. Daneben werden optimierte Einbettungsbauformen untersucht, die eine geringe Zugbeanspruchung garantieren und gleichzeitig einen geringen Massebedarf aufweisen. Aufbauend auf den Ergebnissen der Parameterstudien ist eine analytische Berechnungsvorschrift abgeleitet sowie die statische und dynamische Tragfähigkeit des keramischen Gleitlagers experimentell nachgewiesen worden. Im Ergebnis der Forschungsarbeit steht die mechanische Einsatzfähigkeit des keramischen Gleitlagers auf Basis von Siliziumnitrid (Si3N4). Sowohl die statische als auch die dynamische Tragfähigkeit konnte bis zu einer Flächenpressung von mindestens 150 N/mm² und bei einer Lastfrequenz von 12,5 Hz nachgewiesen werden.
8

Stavebně technologický projekt demolice a stavby mostu / CONSTRUCTION-TECHNOLOGY PROJECT OF BRIDGE DEMOLITION AND BRIDGE CONSTRUCTION

Hofírek, Radovan January 2018 (has links)
This diploma thesis deals with the demolition of a bridge located at the D1 motorway from Prague to Brno. The bridge no longer meets the load and width requirements of today´s standards. The thesis also deals with the construction of a new bridge, which will be expanded into D28/120 category. This expansion will allow for provisory use of the carriageways of one half of the motorway in both directions. The whole reconstruction is very time consuming that is the reason the new bridge is made of prefabricated pre-tensioned girders with a composite bridge deck. This can save time and the new bridge can be open for service in a shorter period of time.
9

Nájemní objekt Campus Bohunice – stavebně technologický projekt / The lease object Campus Bohunice - construction technology project

Platzerová, Veronika January 2018 (has links)
The subject of this diploma thesis is the construction and technological solution of the construction of the campus building Bohunice - object C. This building is a new building located on several unfinished parcels. The diploma thesis contains technical reports, technological regulations of the selected works, control and test plans for these works, design of the machine group, the transport relations in the narrower and wider surroundings of the construction, the budget budget, the timetable, the design and realization of the tower cranes.
10

Stavebně technologický projekt sportovní haly Svojsíkova v Českém Těšíně / Construction technology project of sports hall Svojsíkova in Český Těšín

Rozsypal, Patrik January 2019 (has links)
This diploma thesis focuses on the construction technology project of sports hall Svojsíkova in Český Těšín. The aim of this diploma thesis is to process main documents related to construction of the solved sports hall. This means, in particular, to design the construction site facilities and main construction machinery, to process time schedule, budget and technological prescription of floor structures together with control and test plan and construction details.

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