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Experimental Procedures for Operational Modal Analysis of a Power Pack on a Drill RigNilsson, Oscar January 2017 (has links)
All structures have modal properties such as natural frequencies and damping. In engineeringit is often of interest to estimate these modal properties for certain structures, to be used whenmodelling for example fatigue. This is done by computing them from finite element models, by using experimental measurements or both. In the case of doing both, a finite elementmodel is usually established first and adjusted to fit measurements from experiments. Atlas Copco Rock Drills AB is the company where this thesis has been performed and the subject is experimental procedures related to estimating modal properties of the so calledpower pack, which essentially is a modularised engine and hydraulic power source of an Atlas Copco drill rig. Their current method for estimating these properties is a classical procedure which makes use of an impact hammer that an operator strikes the power pack with to induce excitation. Due to concealment of behind other parts the power pack when mounted inside the drill rig, the number of places where the operator is able to strike the power pack in is limited. Another problem with the current procedure is that it can be difficult to strike the power pack with a strong enough impulse to generate reliable results. In this thesis a new experimental procedure for Atlas Copco to use is suggested. It is based on operational modal analysis (OMA), which uses the machinery's excitation from its operational conditions to compute modal estimates. A comparison between different experimental procedures have been done and the suggested procedure is the following: excitation by engine sweep; modal identifcation by the PolyMAX method and mode shape scaling by the harmonic scaling method. An experiment was performed to compare two OMA procedures.The suggested procedure is the one that generated the better results of the two.
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Operational Modal Parameter Estimation from Short Time-Data SeriesArora, Rahul 03 June 2014 (has links)
No description available.
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Ablaufszenarien fuer Client-Server Anwendungen mit CORBA 2.0Falk, Edelmann 12 November 1997 (has links)
Die Common Object Request Broker Architecture (CORBA) der
Object Management Group (OMG) bietet die Chance, nicht nur
eine Plattform fuer neue verteilte Anwendungen zu sein,
sondern erlaubt es auch, bestehende Anwendungen und
Altsoftware hersteller- und systemuebergreifend zu
integrieren. Diese Eigenschaft hebt CORBA von anderen
Programmierplattformen ab und gibt CORBA das Potential,
eine aussichtsreiche Basis fuer kuenftige Anwendungssysteme
zu sein.
Das Ziel dieser Studienarbeit besteht darin, die
Umsetzbarkeit verschiedener Interaktionsarten in CORBA zu
untersuchen und an Beispielen praktisch auszuprobieren.
Moegliche Ablaufformen aus der Literatur, aus den Systemen
DCE und MPI und anhand eigener Ueberlegungen werden im
ersten Teil dieser Arbeit systematisch zusammengefasst.
Danach folgt eine ausfuerliche Behandlung der Architektur
von CORBA und der hier moeglichen Ablaufformen und
Interaktionsszenarien. Abschliessend werden acht
verschiedene Versionen eines einfachen verteilten
Woerterbuches vorgestellt, um einige der in CORBA
realisierten Konzepte am praktischen Beispiel zu
verdeutlichen. Als CORBA-Plattform stand Orbix-MT 2.0.1
(multi-threaded) der Firma IONA Technologies Ltd. unter
Solaris 2.x zur Verfuegung.
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Operational Modal Analysis of the Stockholm Waterfront Congress CentreGrundström, Ulrika January 2010 (has links)
No description available.
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Understanding the Sequence-Specificity and RNA Target Recognition Properties of the Oocyte Maturation Factor, OMA-1, in Caenorhabditis elegans: A DissertationKaymak, Ebru 28 April 2016 (has links)
Maternally supplied mRNAs encode for necessary developmental regulators that pattern early embryos in many species until zygotic transcription is activated. In Caenorhabditis elegans, post-transcriptional regulatory mechanisms guide early development during embryogenesis. Maternal transcripts remain in a translationally silenced state until fertilization. A suite of RNA-binding proteins (RBP’s) regulate these maternally supplied mRNAs during oogenesis, the oocyte-to-embryo transition, and early embryogenesis. Identifying the target specificity of these RNA-binding proteins will reveal their contribution to patterning of the embryo. We are studying post-transcriptional regulation of maternal mRNAs during oocyte maturation, which is an essential part of meiosis that prepares oocytes for fertilization. Although the physiological events taking place during oocyte maturation have been well studied, the molecular mechanisms that regulate oocyte maturation are not well understood.
OMA-1 and OMA-2 are essential CCCH-type tandem zinc finger (TZF) RBP’s that function redundantly during oocyte maturation. This dissertation shows that I defined the RNA-binding specificity of OMA-1, and demonstrated that OMA-1/2 are required to repress the expression of 3ʹUTR reporters in developing oocytes. The recovered sequences from in vitro selection demonstrated that OMA-1 binds UAA and UAU repeats in a cooperative fashion. Interestingly, OMA-1 binds with high affinity to a conserved region of the glp-1 3ʹUTR that is rich in UAA and UAU repeats. Multiple RNA-binding proteins regulate translation of GLP-1 protein, a homolog of Notch receptor. In addition to previously identified RBP’s, we showed that OMA-1 and OMA-2 repress glp-1 reporter expression in C. elegans oocytes.
Mapping the OMA-1 dependent regulatory sites in the glp-1 mRNA and characterizing the interplay between OMA-1 and other factors will help reveal how multiple regulatory signals coordinate the transition from oocyte to embryo but the abundance of OMA-1 binding motifs within the glp-1 3ʹUTR makes it infeasible to identify sites with a functional consequence. I therefore first developed a strategy that allowed us to generate transgenic strains efficiently using a library adaptation of MosSCI transgenesis in combination with rapid RNAi screening to identify RBP-mRNA interactions with a functional consequence. This allowed me to identify five novel mRNA targets of OMA-1 with an in vivo regulatory connection. In conclusion, the findings in this dissertation provide new insights into OMA-1 mediated mRNA regulation and provide new tools for C. elegans transgenesis. Development of library MosSCI will advance functional mapping of OMA-1 dependent regulatory sites in the target mRNAs. Extending this strategy to map functional interactions between mRNA targets and RNAbinding proteins in will help reveal how multiple regulatory binding events coordinate complex cellular events such as oocyte to embryo transition and cell-fate specification.
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Modeling Liver Diseases Using Hepatic Cell MicroarraysRoth, Alexander David 13 December 2018 (has links)
No description available.
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Evaluación del daño en estructuras esbeltas y metodología de refuerzo con materiales compuestos frente a acciones dinámicasBru, David 07 September 2020 (has links)
The research presented in this doctoral thesis focuses on damage assessment in slender structures and on the methodology of reinforcement by means of composite materials. In particular, the dynamic behaviour of masonry belfries and industrial chimneys, as well as concrete buildings constructed in the coastal area of the Spanish east coast in the mid-20th century, has been analysed. These analyses have been carried out based on the study of several specific structures. In relation to the former, research has been carried out on the bell tower of Fiesole Cathedral, Italy. The main objective of the research is to evaluate the problems of dynamic interaction between the inertial forces associated with the swing of the bells and the main structure of the bell tower. In relation to the second structural typology, a study has been carried out to evaluate the origin of the current state of cracking of the industrial masonry chimneys, as well as to evaluate the damage associated with the problems of collapse that they present at the top of the chimneys. This study has focused on two industrial chimneys located in the municipality of Manises, Valencia, and Agost, Alicante. Finally, in relation to the third structural typology analysed, a third study was carried out on the Torre Adoc 10, located in the coastal area of the city of Alicante. The main objective of this research is to analyze the combined effect of corrosion and seismic action after forty years of corrosion processes on the structure, evaluating the distribution of the damage pattern by analyzing the capacity and demand curves. Finally, an analysis related to the seismic vulnerability of industrial masonry chimneys has been carried out, focusing on the chimney of Agost, Alicante. On the basis of this analysis the pattern of damage to the structure has been defined, and a system of reinforcement using composite materials capable of preventing the structural collapse of the stack has been proposed and sized. The content of this doctoral thesis has been structured in three phases according to the development of the work carried out. In this sense, the first phase is called "Phase of structural characterization", the second phase, "Phase of definition of the numerical model" and finally the third phase, "Phase of definition and analysis of variables". During the development of the first phase, the geometric characterisation of the structures is carried out, as well as the characterisation of the materials by means of laboratory tests or on the basis of the available literature. The results obtained from the process of characterisation of the materials allow the mechanical characteristics of the mortars and brick units to be known, but in addition, analysis at a microstructural level of the samples allows the presence of contaminating agents and expansive salts to be determined, which allows the problem of the damage analysed to be put into context later with the numerical models. Finally, the dynamic characterisation of the structures is carried out with the aim of finding out the modal parameters that allow the subsequent calibration of the numerical models. In the second phase, the numerical models are generated defining the behaviour of the materials in the linear and non-linear range. In addition, the models are calibrated from the experimental data obtained in the previous phase, or by means of experimental data from the consulted bibliography. During this phase the results of the calibration have been analysed using genetic algorithms of the Fiesole bell tower, and the influence of the lateral confinement of the tower on the modal response of the structure has been determined. Finally, during the third phase, the variables associated with the damage assessment of the modelled structures are analysed. In this sense, the first variable analyzed focuses on the effect of the swing of the bells. This study analyses the effect of the velocity, the angle of oscillation and the position of the bells along the height of the tower, in order to determine the range of operation of the bells to avoid damage to the structure. In addition, the influence of the harmonics of the inertial force of the bells on the determination of the real response of the structure is evaluated and compared with the simplified solution proposed by DIN 4178. The second variable focuses on the study of the origin of the current state of damage present in masonry industrial chimneys. This study is analysed from two points of view. On the one hand, the effect of the thermal action during the normal operation of the chimney is evaluated, and on the other hand, the effect of the increase in volume of the metallic elements due to corrosion, arranged on the inside of the chimney, is assessed. Finally, the third variable is related to the analysis of the seismic vulnerability of the Agost masonry industrial chimney, and the reinforced concrete building, Torre Adoc 10. This study analyses the seismic demand through the use of elastic response spectra, and compares the capacity of the structure through a sectional analysis, and through a non-linear pushover analysis. From the results, the damage pattern in both structures is analyzed, and the influence of corrosion in the case of the reinforced concrete building is evaluated. Finally, the results of the analysis of the seismic vulnerability in the industrial chimney allow us to propose a reinforcement system using composite materials capable of preventing the collapse of the structure.
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Norra Tornen: Making exclusive living inclusiveWilner, Oscar January 2020 (has links)
Today our city cores are being transformed. Not only have they been transformed from a place of production to a place of consumption, but more recently also the city core as a place of work are being challenged by increasing land prices and the desire to live centrally and urban. An urban lifestyle has in some ways become an exclusive benefit for the most wealthy, and the tall residential towers symbolizes this new urban, transnational elite, that wants the qualities of a living city center but prefers to live high up in the sky. Though this elite sometimes never lives there, since they only see the apartments as investments, as a “money deposit”. These buildings increase gentrification and segregation since they push up the housing prices of the city cores and provide no public functions, we get excluding cities rather than including. In my thesis project I speculate how we can prevent our city centers from becoming an excluding and exclusive gated community, and I develop a general redesign strategy for the exclusive residential tower typology. I have searched for a collective rather than individualistic approach, that considers both environmental and social sustainability.
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CELEBRATING EXTINCTION? The Disconnect Between Reality and Media Representation of Bluefin Tuna in JapanFukui, Gene 04 June 2014 (has links)
No description available.
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Os recursos hídricos transfronteiriços como direito transindividual internacional : uma proposta de estruturação da Organização Mundial da Água (OMA) e do Fundo Monetário Internacional de Proteção a Água (FMIPA)Flores, Karen Müller 06 August 2010 (has links)
A água, assim como o ar, é vital à sobrevivência dos seres bióticos. Para muitos autores há distinção entre "água" e "recurso hídrico". O termo "água" designa o elemento natural, enquanto a expressão "recurso hídrico" representa o valor econômico; assim, compreendido como direito fundamental e mercadoria, respectivamente. Os recursos hídricos transfronteiriços internacionais (que banham mais de um estado soberano) são classificados em superficiais (rios, lagos, represas, açudes, entre outros) ou subterrâneos (aqüíferos); As reservas hídricas superficiais são de mais fácil acesso, porém escassas; já as reservas subterrâneas são de difícil acesso, mas abundantes; contudo, em ambos os casos a utilização deverá ser racional. A escassez dos recursos hídricos é quanti-qualitativa. O ser humano enquanto pessoa consciente é capaz de alterar o rumo do planeta, por meio da construção de uma nova identidade, influindo na formação de uma nova cultura. Conceitos como supranacionalidade e transnacionalidades passam a ser aceitos em nome da preservação da biodiversidade e conseqüência do próprio homem, enquanto parte do sistema ambiental, ou seja, a sociedade global passa da fase de coexistência a fase de cooperação e solidariedade. Isso porque, as relações econômicas, políticas, sociais, culturas e tecnológicas são hoje transnacionais, assim como os impactos ambientais. Assim, a proposta de elaboração da Organização Mundial da Água (OMA), organismo supranacional de proteção dos recursos hídricos transfronteiriços internacionais, e do Fundo Monetário Internacional de Proteção à Água (FMIPA) desempenha significativo papel na conscientização dos seres humanos quanto à importância e a necessidade de mudanças urgentes em relação ao tema. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-30T17:38:37Z
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