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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

To Move an Obelisk / Att flytta en obelisk

Jansson, Wilhelm January 2019 (has links)
Today, there are more Egyptian obelisks outside of Egypt than there are left where they were made. The obelisks are certainly beautiful, but what lies beneath are uncountable hours, days and years of work. Work which made the obelisks end up where they are today. From quarrying these enormous pieces of stone by smashing rock against rock, to building ships without equal for their transportation. It is hard to understand the amount of resources, manpower and organization that went into creating these tall monuments. Therefore, this study will attempt to examine each step in transporting the obelisks, from the quarry to their destination. Where theories collide, the study will weigh them against each other critically to give a fuller account of the transportation of the obelisks of Egypt. This study will begin by presenting a background, or basis, which will be further built upon as it progresses. The first chapter is mainly focused around the circumstance of transportation, along with giving a basic description of obelisks as individual objects. The next step lies in studying the general shipbuilding techniques used in ancient Egypt. This in turn will help in understanding the obelisk ships and the loading and unloading of these vessels. The obelisk ships and their loading will be the focal point of this study. The mainstay of the sources used for this study comes from earlier theories. The primary sources of this study will mainly consist of textual remains along with depictions. / Idag finns det fler obelisker utanför Egypten än vad det finns kvar innanför dess gränser. Obeliskerna är helt klart vackra, men vad som ligger under ytan är oräkneliga timmar, dagar och år av arbete. Arbete som gjorde att obeliskerna hamnade på den plats de är idag. Från att bryta dessa enorma stenblock genom att slå sten mot sten, till att bygga skepp utan dess like för deras transport. Det är svårt att förstå den enorma mängd resurser, arbetskraft och ren vilja som krävdes för att skapa dessa höga monument. Av denna anledning kommer den här studien att försöka närma sig varje steg i transporten av obelisker, från stenbrottet till deras destination. Där teorier kolliderar, kommer denna studie att väga dem mot varandra kritiskt för att ge en mer komplett inblick i transporten av antika Egyptiska obelisker. Denna studie kommer att börja med att presentera en bakgrund, eller bas, som kommer att byggas vidare på under arbetets gång. Studiens första del fokuserar  på omständigheterna för transporten, samt med att ge en grundläggande beskrivning av obelisker som individuella objekt. Det nästkommande steget ligger i att studera de tekniker som användes för skeppsbygge i det antika Egypten. Detta kommer i sin tur underlätta för förståelsen av obeliskskepp och avlastning samt pålastning av dessa farkoster. Obeliskskeppen och deras lastning kommer att utgöra huvuddelen i denna studie. Huvuddelen av källorna som använts för denna studie kommer från tidigare teorier. Primärkällorna som använts består till största del av textuella lämningar samt avbildningar.
42

Modelamento numérico da técnica de normalização linear para determinação de curvas J-R / Numerical modeling of the linear normalization technique for J-R curves determination

Angelo Antonio Colafemea 20 August 2001 (has links)
Neste trabalho os resultados da metodologia de normalização de E. D. Reese e K. H. Schwalbe para a obtenção de curvas J-R, são comparadas com aquelas obtidas pela tradicional Técnica de Variação de Flexibilidade Elástica. Ambos os métodos foram aplicados à um aço de grau nuclear A508-CL3A, quando vários corpos-de-prova miniaturizados 0.394TC[S], foram testados em temperaturas típicas de operação de vasos de pressão nuclear. Corpos-de-prova miniaturizados formam tratados termicamente tentando simular o comportamento exibido pelos aços estruturais quando submetidos à diferentes níveis de exposição de nêutrons, sendo que outros foram ensaiados na condição de como-recebidos. Todos os procedimentos experimentais e analíticos empregados neste estudo foram totalmente computadorizados, incluindo aquisição e refinamento dos dados e o traçado da curva J-R. Esta última foi realizada conforme a mais recente versão das normas ASTM, denominada ASTM-E1820. As variáveis avaliadas influentes do comportamento das curvas de J-R, incluem o incremento de propagação de trinca e o número de pontos de dados de carga versus deslocamento. Também foi analisada a efetividade do método de normalização quando comparada com a técnica de variação de flexibilidade elástica. Os resultados desta pesquisa mostraram que a normalização é uma metodologia confiável e muito simples, tão logo a programação de software seja desenvolvida, para ser aplicada em uma vasta variação de comportamentos mecânicos como amostrados neste estudo. / In this research, results from Reese; Schwalbe (1993) linear normalization methodology for deriving J-R curves are compared to those obtained from the traditional unloading elastic compliance technique. Both methodologies were applied to a nuclear grade steel A508-CL3A. Several miniaturized 0.394TC[S] specimens, were tested at typical NPV operating temperatures. Small scale testpieces were heat treated aiming to simulate the embritlemment exhibited by the structural steel when submitted to different levels of neutron exposure, whereas other specimens were tested in the as-received condition. All experimental and analytical procedures employed in this study have been fully computerized, including data acquisition, data refinement and J-R curve plotting, when the guidelines supplied by most recent version of ASTM standard for J-R curves, namely ASTM-E1820, were followed. The assessed variables affecting J-R curves behavior comprised crack propagation increment, number of load-Ioad line displacement data points, and it was also analyzed the agreement of the normalization method when compared to the compliance technique. Research results have shown that linear normalization is a trustworthy and very simple methodology to be applied in a vast range of mechanical behavior as sampled in this study, as long as computer programming is employed.
43

A Detailed Analysis For Evaluation Of The Degradation Characteristics Of Simple Structural Systems

Kurtman, Burak 01 May 2007 (has links) (PDF)
Deterioration in the mechanical properties of concrete, masonry and steel structures are usually observed under repeated cyclic loading in the inelastic response range. Therefore such a behavior becomes critical when these types of structures are subjected to ground motions with specific characteristics. The objective of this study is to address the influence of degrading behavior on simple systems. The Structural Performance Database on the PEER web site, which contains the results of cyclic, lateral-load tests of reinforced concrete columns, are employed to quantify the degradation characteristics of simple systems by calibrating the selected degrading model parameters for unloading stiffness, strength and pinching of a previously developed hysteresis model. The obtained values of parameters from cyclic test results are compared with the recommended values in literature. In the last part of the study, response of SDOF systems with various degradation characteristics are investigated using a set of seismic excitations recorded during some major earthquakes. The results indicate that when all the degradation components are combined in a structural system, the effect of degradation on response values becomes much more pronounced.
44

Investigation Of Fracture Behavior Of Steel/steel Laminates

Simsir, Mehmet 01 April 2004 (has links) (PDF)
A study is carried out into fracture behavior of steel/steel laminates both experimentally and through finite element analysis (FEM). The laminates produced by hot pressing consisted of low carbon and medium carbon steels with two volume fractions / 0.41 and 0.81. Fracture toughness, JIC has been measured using partial unloading technique assuming a critical value of crack extension. The technique is initially applied to monolithic material and then to the laminates in crack divider orientation. Evaluation of fracture toughness of laminates indicates that there is a substantial improvement of JIC with increase in the volume fraction. The systems under study were also evaluated by FEM modeling with the use MARC package program. To evaluate JIC, the problem has been evaluated in several steps / first two-dimensional plane strain problem is considered. This is followed by three-dimensional case and then by an artificially layered system, all for monolithic materials. Values of JIC derived were close to one another in all cases. Following this verification, the method, as implemented in layered monolithic system, was applied to laminates. This has shown that JIC of laminates can be predicted using FEM analysis, including the delamination. Values of JIC varied in the same manner as the experiment verifying that fracture toughness in the current system increases with increase in volume fraction. It has been concluded that modeling as implemented in this work can be used for useful composite systems incorporating hard/brittle reinforcements both in crack divider and crack arrester orientation.
45

Analýza manipulačních prostředků a zařízení pro realizaci ložných operací v zemědělství / Analysis of handling equipment and device for realization of loading operations in agriculture

ŠAFRÁNKOVÁ, Eva January 2014 (has links)
The target of thesis is to analyze handling equipment and device for realization of loading operations in agriculture and provide proposals and principles for optimal usage of applied handling equipment and device. The characteristics and clasifications of materials in agriculture, loading operations and transportation, listing of applied handling equipment and device for realization of such processes are stated in literary survey of this work. Next part of the work focuses on selection of modern handling equipment, device and producers ( domestic and international) available at current market and defines factors influencing the prefered choice to use particular handling equipment and device for loading processes on farms and in other agricultural environment. A part of the analysis is data and information acquisition of particular farm and review of loading processes in agriculture connected to applicable handling equipment and device, furthermore, currently used handling equipment and device with proposal to optimalization.
46

Studie logistické koncepce distribučního skladu / The Study of Logistic Conception of Distribution Stock

Kubala, Jakub January 2008 (has links)
This master thesis “The Study of Logistic Conception of Distribution Stock” deals with global operation of distribution stock in its entire levels with target to design efficient communication methods with costumer and suppliers. Based on analyses of actual situation it effort to identify general poverties and find proper methods of it’s solution. First chapter is based on theoretical part. It explains basic logistical principals as one of the elements of each organization. Second chapter introduces Arcelor Distribuce CZ Company from work place way of look. Third chapter is dedicated to risk management as a theory of identification and evaluation actual or potential risks company may treat with. Fourth chapter the largest one defines particular issues company has to deal with and issues which block company’s way of growth. Further there are introduced steps heading to solve these problems. This thesis sets a target to identify and design solutions of main problems in communication in the first place, which block company’s natural evolution.
47

Effect of Early Life Physical Inactivity Level on Muscle Health During Early Postnatal Development

Smith, Austin 02 August 2022 (has links)
No description available.
48

Calculation of Tidal Volume based on EMG-activity of the Diaphragm

Micski, Erik, Ottosson, Ulrika January 2017 (has links)
The objective of the thesis was to evaluate the possibility to calculate the unloading distribution between a ventilator and a patient using a new mathematical modelling of the breathing patterns. The modelling used today is considered to lack sufficient precision for clinical use, and is a somewhat simplified model. To evaluate the possibility of a new model, a volunteer test was carried out - recording data such as Edi, pressure, volume and flow. Using this data, and by using a more complex model, tidal volume was estimated and compared to the measured data. The results did not imply any improvement compared to the simpler model regarding the accuracy and the variability. However, more work should be done in this area, as time deficiency prevented further analysis.
49

Airport ground operations through the lens of human-technology systems : a descriptive case study of ground operations at a Swedish airport

Carlson, Valerie, Lindblom, Bénédicte January 2020 (has links)
Summary Aim: The aim with the study was to explore the work conditions of the Ground staff performing unloading and loading from an HTO perspective, and to identify areas for improvement. Research questions: 1. Which factors are important for the work performance? 2. To what degree do the employees follow the work instructions regarding the use of the equipment on the ramp? 3. Which recommendations can be provided to improve work performance at ramp operations and minimize risks for accidents? Background: Ramp operations have, according to Studic et al., (2017), repeatedly been estimated as one of the areas with the highest, still increasing, safety risks. Passenier, Sharpanskykh and de Boer (2015) also confirms how the work within the ramp operations, and performance of unloading and loading, is an area with high risks of injuries and deaths. Methods: The study was conducted with a qualitative research approach and Descriptive Case study design (Baxter & Jacks, 2008). Results: Five categories were found; time pressure, “safety mindset”, education, culture and equipment. The findings also showed that the employees prioritize the safety of the aircraft rather than their own safety. Conclusions: Out of the five factors, time pressure and equipment are the factors in the environment which the respondents have to work in line with to make it function in the environment.
50

Análise de falhas e suas consequências na operação de navios transportadores de Gás Natural Liquefeito (GNL). / Analysis of failures and their consequences in the operation of tank carriers transporting Liquefied Natural Gas (LNG).

Roldán Silva, Dennis Wilfredo 06 December 2012 (has links)
No Brasil a geração de energia elétrica é predominantemente baseada no uso de fontes renováveis e obtida por meio de centrais hidroelétricas. Ainda assim é necessária a diversificação das fontes de suprimento de energia para a geração de eletricidade quando o recurso hídrico for escasso. Uma alternativa é utilizar gás natural como combustível para as usinas termoelétricas, como vem sendo introduzido na matriz energética de outros países, permitindo a diversificação das fontes energéticas dos mesmos. A indústria do gás natural, assim como outras atividades industriais, não está isenta de acidentes que podem provocar graves consequências à integridade das pessoas e das propriedades. Por este motivo, é necessário desenvolver estudos para determinar quais são as possíveis causas que poderiam ocasionar estes acidentes, e quais são os possíveis cenários associados a estas falhas especificamente na área do transporte de GNL (Gás Natural Liquefeito). É neste contexto que este trabalho de pesquisa tem por objetivo desenvolver um método, baseado nas técnicas de análise de risco, que permita identificar os principais cenários de falha associados à ocorrência de um vazamento de GNL ou de boil-off durante as operações de carga e/ou descarga de navios. Neste cenário, considera-se a presença das barreiras de proteção destinadas a conter esse evento iniciador de perigo no sistema de carga e descarga do navio transportador de GNL, quando o navio está atracado no porto. Adicionalmente à apresentação do método, e como resultado do trabalho, são identificados quais os componentes que pertencem ao circuito de carga e descarga de GNL, e que tenham uma categoria de risco denominada como Crítica (C), Moderada (M) ou Não Crítica (NC). Finalmente, a implantação do método propõe medidas que ajudam a diminuir o nível de risco associado aos componentes denominados críticos, a fim de garantir uma operação segura e livre de acidentes que ponham em risco a integridade dos operadores, dos equipamentos e do ambiente. / Although the electricity generation in Brazil is predominantly based on renewable sources and obtained by means of hydroelectric power plants, it is still necessary to diversify sources of energy supply to generate electricity when the water resource is scarce. An alternative is the use natural gas as fuel for power plants, once it has been introduced in the energy matrix of other countries, allowing the diversification of their energy sources. The natural gas industry, as well as other industrial activities, is not free from accidents, which can cause serious consequences to the integrity of people and properties. For this reason, it is necessary to develop studies to determine what are the possible causes that could lead to serious accidents and what are the possible scenarios of these faults specifically in the area of LNG (Liquefied Natural Gas) transportation. In this context, this research aims to develop a method based on risk analysis concepts which identifies the main failure scenarios given the occurrence of LNG or boil-off leakage during ship loading and unloading operations, considering the presence of containment barriers designed to hold this hazard initiator event in loading and unloading system of the LNG carrier when the ship is in harbor. In addition to the method presentation this research identifies which are the components of LNG loading and unloading circuit, which have a risk category classified as Critical (C), Moderate (M) and NonCritical (NC). Finally, the method implementation allows the proposal of safety and maintenance measures to help reducing the risk level in order to ensure safe operation, free of accidents that endanger the integrity of the operators, the equipment and the environment.

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