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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Modifikace provozních podmínek stroje ALIMAK - SCANDO / Modification of work conditions ALIMAK - SCANDO machine

Němec, Jan January 2011 (has links)
The theme of this master´s thesis with theme the modification of work conditions, it´s aim is to analyse existing and modified operating conditions of the machine and make their comparison. This work includes frame stress analysis, surface burdened by wind, the stability of the location and control of capacity at endurance.
42

Rám pro výtahový stroj / Frame for elevator machine

Sokol, Filip January 2011 (has links)
The diploma thesis deals with replacement of frame for elevator machine. Original frame was made from metallurgic profile and was replaced by bending sheet metal. The thesis contains strength analysis and calculation of original construction solution as well as the new one. Strength calculation was done in program I-DEAS for two load sets: full load in regular operation and immediate cessation of elevator machine in full speed.
43

Kontinuální elevátor pro přepravu zboží / Continuous vertical conveyor for transport the goods

Zálešák, Martin January 2014 (has links)
This diploma thesis deals with the existing of transportation unit products and designing of a better conceptual solution of continuous elevator with fixed section of a gravity and roller conveyor. This type of conveyor is specified mainly for the transport of boxed products from the lower floor to the another. The diploma thesis is substantiate by the proposal of assemblies machines. It includes a complete 3D design, engineering and functional solution that is supported by basic strength and the check calculations. The attachments consist of the drawings of the proposed facility.
44

Maskininlärning som möjligt planeringsverktyg för mindre serviceföretag : En studie i maskininlärning för verksamhetsplanering inom hissbranschen hos fallstudieföretaget S:t Eriks Hiss AB / Machine Learning as a complementary planning tool for SME’s in the maintenance industry : A study of machine learning for operational planning within the elevator sector at S:t Eriks Hiss AB

Assarsson, Fabian, Kjellin, Gustav January 2016 (has links)
I följande rapport visar vi att maskininlärningsalgoritmer från lättillgängliga bibliotek kan vara värdefulla verktyg, vid analys av företagsdata. Vi föreslår en ny metrik för frekvensanalys av oplanerade underhållsbesök genom en fallstudie inom hissbranschen och ger också företaget i fråga, S:t Eriks Hiss i Stockholm, ett geografiskt kundsegmenteringsalternativ, baserat på K-Meansklustring. Vi tillhandahåller också en kort diskussion om huruvida resultaten från Anderson et al (2009) och Blakeley et al (2003) skulle kunna utgöra ett analytiskt ramverk för företag i den urbana infrastrukturindustrin. / In this report we show that Machine Learning algorithms from readily available libraries can be useful tools when analyzing company data. We suggest a new metric for analyzing the frequency of unplanned maintenance calls with an elevator maintenance case study, and also provide the company in question, S:t Eriks Hiss, with a K-Means clustered suggestion of geographical customer partitioning. We provide a brief discussion on whether the results from Anderson et al (2009) and Blakeley et al. (2003) could provide an analytical framework for companies in the urban maintenance industry. A weak negative correlation between profitability and our suggested metric indicate that so is the case and makes for interesting further enquiry.
45

The Steep Climb to Low Earth Orbit: A History of the Space Elevator Community's Battle Against the Rocket Paradigm

Pearson, Derek J. 13 June 2022 (has links)
This thesis examines the growth of the space elevator community in America from 1975 to 2010. It argues that the continued practical failures of the space elevator, a proposed technology for efficiently transporting payloads and people into space without conventional propulsion sources, resulted from a technological paradigm built around the rocket and supported by a traditional engineering culture. After its triumph in landing men on the Moon from 1969 to 1972, the United States' National Aeronautics and Space Administration (NASA) sought to advance novel concepts for further space exploration, but it fumbled in pursuing nontraditional notions of escaping the atmosphere such as the space elevator. Employing interviews with space elevator advocates Bradley Edwards and Michael Laine and other primary and secondary sources, this thesis also draws on concepts such as technological paradigms, engineering cultures, and the technological sublime. It concludes by demonstrating how success eluded the marginalized space elevator researchers who found themselves grappling with the vast social and technical system that supported the rocket's hegemony. / Master of Arts / This thesis examines the growth of the space elevator community in America from 1975 to 2010. It argues that the continued practical failures of the space elevator, a proposed technology for efficiently transporting payloads and people into space without conventional propulsion sources, resulted from a technological paradigm built around the rocket and supported by a traditional engineering culture. The technological paradigm of the rocket encompassed all of the people and practices that made the rocket work. After its triumph in landing men on the Moon from 1969 to 1972, the United States' National Aeronautics and Space Administration (NASA) sought to advance novel concepts for further space exploration, but it fumbled in pursuing nontraditional notions of escaping the atmosphere such as the space elevator. Much of this failure is owed to an engineering culture within NASA that looked down upon challenging the rocket. This thesis demonstrates how success eluded the marginalized space elevator researchers who found themselves grappling with the vast social and technical system that supported the rocket's hegemony.
46

Aplicação de redes de Petri interpretadas na modelagem de sistemas de elevadores em edifícios inteligentes. / Aplication of interpreted Petri nets for modelling elevators systems in intelligent buildings.

Gladys Deifan Bastidas Gustin 27 January 2000 (has links)
O sistema de elevadores como equipamento para o transporte vertical de pessoas e bens é um componente fundamental no projeto de edifícios e, neste âmbito, a disponibilidade e eficiência do seu serviço deve ser objeto de cuidadosa análise em função de sua influência no desempenho e produtividade das atividades dos usuários do prédio. Neste contexto e considerando especificamente os edifícios inteligentes cuja finalidade é a otimização a nível estrutural e funcional do edifício como um todo, e onde a integração entre seus sistemas cumpre um papel fundamental para atingir estes objetivos, o presente trabalho propõe uma metodologia para a modelagem de sistemas de elevadores nestes prédios, que considera a sua integração com outros sistemas prediais. A abordagem empregada no desenvolvimento deste trabalho baseia-se na caracterização dos sistemas de elevadores como sistemas a eventos discretos (SED), pois sua dinâmica é definida através da ocorrência de eventos e a manutenção de estados discretos. Assim, na metodologia utiliza-se técnicas derivadas das redes de Petri (redes de Petri interpretadas), de comprovada eficiência para a modelagem, análise e controle de SEDs. Estas ferramentas são usadas através de uma abordagem estrutural, onde o sistema é modelado em diferentes níveis de abstração: um modelo conceitual obtido pelo uso da técnica PFS (Production Flow Schema) em um primeiro nível, e o refinamento deste para modelos funcionais através do uso do MFG (Mark Flow Graph) e suas extensões, onde são preservadas as estruturas das atividades do nível superior e são descritos os detalhes em um nível funcional. A metodologia proposta confirmou ser útil e eficiente para a modelagem do sistema de elevadores em edifícios inteligentes, ao permitir a especificação do modelo funcional de todo o sistema (objeto de controle e sistema de controle) e das estratégias que facilitam a sua integração com outros sistemas prediais / The elevator system as mean for the vertical transport of people and goods is a fundamental component in the design of buildings. The availability and efficiency of this service must be object of careful analysis due to its influence on the performance and productivity of the building users' activities. In intelligent buildings, the purpose is the optimization of its structural and functional levels and where also the integration between all building systems accomplishes a fundamental role to reach these objectives. In this context, this work proposes a methodology for the modeling of elevator systems in these buildings, which consider your integration with others buildings systems. The approach developed in this work is based on the characterization of elevator systems as Discrete Event Systems (DES), since the dynamic behavior is defined through the discrete events and discrete states. The proposed methodology uses techniques, that are derived of interpreted Petri nets, which has been proven as an efficient tool for modeling, analysis and control of DES. In this context, systems are modeled in different levels of abstraction: a conceptual model which is obtained by using the PFS (Production Flow Schema) technique level, and a functional model by using MFG (Mark Flow Graph) and its extensions. The MFG abstraction level describes details in a functional form, where are preserved the description activities of previous levels. The methodology proposal confirmed to be useful and efficient to elevator systems modeling, when allowing the functional specification of the whole system (object of control and control system), and strategies that facilitate its integration with others building systems.
47

Aplicação de redes de Petri interpretadas na modelagem de sistemas de elevadores em edifícios inteligentes. / Aplication of interpreted Petri nets for modelling elevators systems in intelligent buildings.

Bastidas Gustin, Gladys Deifan 27 January 2000 (has links)
O sistema de elevadores como equipamento para o transporte vertical de pessoas e bens é um componente fundamental no projeto de edifícios e, neste âmbito, a disponibilidade e eficiência do seu serviço deve ser objeto de cuidadosa análise em função de sua influência no desempenho e produtividade das atividades dos usuários do prédio. Neste contexto e considerando especificamente os edifícios inteligentes cuja finalidade é a otimização a nível estrutural e funcional do edifício como um todo, e onde a integração entre seus sistemas cumpre um papel fundamental para atingir estes objetivos, o presente trabalho propõe uma metodologia para a modelagem de sistemas de elevadores nestes prédios, que considera a sua integração com outros sistemas prediais. A abordagem empregada no desenvolvimento deste trabalho baseia-se na caracterização dos sistemas de elevadores como sistemas a eventos discretos (SED), pois sua dinâmica é definida através da ocorrência de eventos e a manutenção de estados discretos. Assim, na metodologia utiliza-se técnicas derivadas das redes de Petri (redes de Petri interpretadas), de comprovada eficiência para a modelagem, análise e controle de SEDs. Estas ferramentas são usadas através de uma abordagem estrutural, onde o sistema é modelado em diferentes níveis de abstração: um modelo conceitual obtido pelo uso da técnica PFS (Production Flow Schema) em um primeiro nível, e o refinamento deste para modelos funcionais através do uso do MFG (Mark Flow Graph) e suas extensões, onde são preservadas as estruturas das atividades do nível superior e são descritos os detalhes em um nível funcional. A metodologia proposta confirmou ser útil e eficiente para a modelagem do sistema de elevadores em edifícios inteligentes, ao permitir a especificação do modelo funcional de todo o sistema (objeto de controle e sistema de controle) e das estratégias que facilitam a sua integração com outros sistemas prediais / The elevator system as mean for the vertical transport of people and goods is a fundamental component in the design of buildings. The availability and efficiency of this service must be object of careful analysis due to its influence on the performance and productivity of the building users' activities. In intelligent buildings, the purpose is the optimization of its structural and functional levels and where also the integration between all building systems accomplishes a fundamental role to reach these objectives. In this context, this work proposes a methodology for the modeling of elevator systems in these buildings, which consider your integration with others buildings systems. The approach developed in this work is based on the characterization of elevator systems as Discrete Event Systems (DES), since the dynamic behavior is defined through the discrete events and discrete states. The proposed methodology uses techniques, that are derived of interpreted Petri nets, which has been proven as an efficient tool for modeling, analysis and control of DES. In this context, systems are modeled in different levels of abstraction: a conceptual model which is obtained by using the PFS (Production Flow Schema) technique level, and a functional model by using MFG (Mark Flow Graph) and its extensions. The MFG abstraction level describes details in a functional form, where are preserved the description activities of previous levels. The methodology proposal confirmed to be useful and efficient to elevator systems modeling, when allowing the functional specification of the whole system (object of control and control system), and strategies that facilitate its integration with others building systems.
48

„Kauno grūdų“ elevatoriaus konversija į jaunimo daugiafunkcį gyvenamąjį kompleksą / „Kauno grūdai“ Elevator conversion into Youth Multifunctional Living Complex

Jankus, Arūnas 23 July 2012 (has links)
Magistro baigiamojo darbo tikslas – konvertuoti „Kauno grūdų“ elevatorių į daugiafunkcį jaunimo gyvenamąjį kompleksą, susidedantį iš jaunimo kūrybos ir verslo centro, bendrabučių buvusiuose grūdų silosuose, daugiafunkcio elevatoriaus bei laisvalaikio ir sporto centro. Darbą sudaro trys dalys: analitinė ir tiriamoji (tekstinės) ir projektinė. Analitinėje dalyje pateikta surinkta medžiaga, susijusi su jaunimo bendrabučių ir daugiafunkcių centrų projektavimu bei renovacija, silosų konversija į gyvenamuosius pastatus. Tiriamojoje dalyje pateikta pasirinktos situacijos analizė, problemiškumas, poreikiai ir galimybės, urbanistinės plėtros vizijos. Projektinę dalį sudaro: urbanistinis situacijos maketas (M 1:1000) ir pastato su artimiausia aplinka maketas (M 1:200); projektuojamojo komplekso generalinis planas, planai, pjūviai, fasadai, kambarių silose detalizacija, eksterjero ir interjero perspektyviniai vaizdai. / Master thesis aim is to convert „Kauno grūdai“ elevator to the multifunctional youth living complex, which consists of youth design and business centre, student housing in the former grain silos, multifunctional elevator and leisure and sports centre. The paper consists of analytical, research and project parts. In the analytical part it is presented collected material about design and renovation of student housing and multifunctional youth centres, silos conversions to housing. In the research part it is presented analysis of chosen situation, its problems, requirements and potentials, urban visions. Project part consists of urban situation model (sc 1:1000) and building model with nearest surroundings (sc 1:200); master plan of the designed complex, facades, sections, plans, detailed view of the apartments in silo, exterior and interior perspective views.
49

Vector Controlled Elevator Drive

Gulec, Mustafa Alpertunga 01 May 2006 (has links) (PDF)
In this thesis, a practical vector controlled elevator drive is presented. Indirect vector control of induction machine is investigated in theory and then implemented. Control technique is compared with scalar control and induction machine is compared with dc motor. The operation of the system depends on induction machine parameters, so how to accurately and automatically obtaining of the parameters is also presented. Finally, the elevator system is introduced, the application of this control system to the elevator system is described and a basic elevator control system is simulated.
50

Integration and optimization of a check valve design : A case study at Hydroware AB

Håkansson, Mikael January 2020 (has links)
Constant product development for integration and optimization is a crucial part of companies today. With industrial components comes the challenge with how these parts can be integrated and optimized the best for the system. One example is a hydraulic elevator system, to integrate and optimize the design, the rest of the valve system has to be taken into consideration. This thesis contains the integration and optimization of a check valve solution designed with the help of the product development process in hopes of reducing costs for the manufacturing process for the company. The thesis resulted in an optimized check valve solution with 6 bolts connected with the hydraulic elevator valve system. The requirements were fulfilled but some were not possible to achieve without a physical copy.

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