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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.
391

How Does Skid Design Affect Transportability and Handling of Heavy Machinery? / Hur påverkar designen av en ram, transport och hantering av tunga maskiner?

Eldensjö, Eric, Söderman-Lundqvist, Isidor January 2022 (has links)
At request of the company Climeon, this study was made regarding transportability of skid mounted heavy machinery. The study aimed to investigate what constraining dimensions there might be when transporting by road and sea as well as necessary features that would accommo date lifting, handling, lashing and securing. A literature study was done on the topic of common load carriers and logistics with heavy transports. An interview study was conducted with employees at Climeon to learn how transports are done currently, as well as input on how transports and handling of the machinery could be of higher quality. A conceptual design was made where lifting was simulated with aid of the FEA tool in SolidWorks. An analysis of necessary lashing points was done in Matlab to verify safe transports on road and sea. A dimensional constraint study was made where dimensional breaking points were identified. Price inquiries for these were sent to a forwarding agent to attempt to quantify the cost for transporting skids of various sizes. Trucking is a good mean for transporting within Europe. Roll on-Roll off or flat rack shipping are viable options for transporting large and sensitive machinery when transport by sea is necessary. Lashing the skid could be done mainly with direct lashes in combination with rubber mats for increased friction. A machinery in this order of magnitude can be lifted with a single hook if the structural elements and the lifting eyes are placed positioned in a proper way. / På uppdrag av företaget Climeon gjordes denna studie gällande transporterbarhet av rammonterade maskiner. Studiens mål var bland annat att hitta brytpunkter för dimensionering baserat på väg- och sjötransporter, samt att ta reda på vilka funktioner som behövs för att tillgodose lyft, hantering, surrning och säkring. En literaturstudie utfördes, med fokus på olika lastbärare och logistik kring tunga transporter. För att få djupare insikt i hur transportkvaliteten kan ökas, samt samla in information kring den nuvarande transporthanteringen, utfördes en intervjustudie med anställda från företaget. En konceptuell design togs fram där lyft simulerades med hjälp av FEM-analys i SolidWorks. En analys gjordes i Matlab där nödvändiga surrningspunkter undersöktes för att verifiera säkra transporter på väg och till sjöss. En studie där dimensionella begränsningars inverkan på transportpris gjordes, prisförfrågningar skickades då till en speditör och ett försök gjordes till att kvantiera priset för olika dimensioner på ramen. Lastbil är ett bra sätt att transportera tungt maskineri inom Europa. Roll on-Roll off och flat rack de bästa sättet för transport till sjöss, för stora och ömtåliga maskiner. Maskinen kan säkras i surrningsöglor med spännband eller kedja i direkt surrning i kombination med gummimatta för ökad friktion. En rammonterad maskin i denna storleksordning kan lyftas via ett enkrokslyft om lyftöglor och ramelement är placerade på ett lämpligt vis.
392

Оценка внешнеэкономической деятельности промышленного предприятия в условиях финансового кризиса : магистерская диссертация / Evaluation of foreign economic activity of industrial enterprise in the financial crisis

Паначев, А. А., Panachev, A. A. January 2017 (has links)
This master dissertation is devoted to the actual problem – the lack of a specific methodology for assessing the efficiency of foreign economic activity (FEA) of industrial enterprises in the financial crisis. Therefore was formulated the main goal – development methodological approaches and tools for assessing activation of foreign economic activity of enterprise. First chapter of this dissertation includes review of examines the concept of foreign economic activity, structure, types and other factors influencing on efficiency. Also was describes the main methods and approaches to evaluating the effectiveness of FEA which are also using by industry. In addition, considers such a phenomenon like the financial crisis, explores the main types and causes, in particular, special attention was paid to the events of 2014. As well was nominated the hypothesis about the positive effect of the financial crisis on the foreign trade export enterprises which is works in raw materials and steel direction. In second Chapter was highlighted and described the object of study (OAO NLMK), in his example was evaluated the efficiency of foreign economic activity by using previously identified metrics. Likewise we study the impact of currency volatility on performance indicator from trade deals in dynamics. In third Chapter was developed the algorithm, including step-by-step instructions for the assessment of the external economic activity of industrial enterprise taking into account influence of external factors. Also was offered options necessary responses to changes in the external environment, it will allow to effectively adapt the FEA under the changes, and to reveal reserves of increase of efficiency. This algorithm is a scientific novelty of this dissertation research. Dissertation research located on 107 pages, which has 18 tables and 19 figures, when writing was used 52 bibliographical sources. / Данная магистерская диссертация посвящена актуальной проблеме – отсутствию определенной методики оценки эффективности внешнеэкономической деятельности (ВЭД) промышленного предприятия в условиях финансового кризиса. В связи с чем сформулирована основная цель ¬– разработка методических подходов и инструментария к оценке активизации ВЭД предприятия. В первой главе данной работы рассмотрены понятия внешнеэкономической деятельности, ее структуры, видов и основных факторов, влияющих на ее эффективность. Так же рассмотрены основные методы и подходы к оценке эффективности ВЭД, так же проанализированы существующие показатели эффективности, которые применяются промышленными предприятиями. Кроме того, рассмотрен такой феномен, как финансовый кризис, исследованы основные виды и причины возникновения, в частности особое внимание уделялось событиям 2014 года. Выдвигается гипотеза о положительном эффекте финансового кризиса на ВЭД предприятий – экспортеров сырья и металлопродукции. Во второй главе выделяется и описывается объект исследования (ПАО НЛМК), на его примере производится оценка эффективности внешнеэкономической деятельности при помощи ранее выявленной системы показателей. Так же в динамике изучается влияние валютной волатильности на показатель эффективности от внешнеторговых сделок. В третей главе разрабатывается алгоритм, включающий пошаговую инструкцию по оценке внешнеэкономической деятельности промышленного предприятия, учитывающий влияние внешних факторов. Так же предложены варианты необходимых мер реагирования на изменения внешней среды, данный подход позволит эффективно адаптировать ВЭД под изменения, а так же выявлять резервы повышения эффективности. Алгоритм представляет собой научную новизну данного диссертационного исследования. Диссертационное исследование находится на 107 страницах, на которых размещены 18 таблиц и 19 рисунков, при написании было использовано 52 библиографических источника.
393

Experiments, Constitutive Modeling, and Multi-Scale Simulations of Large Strain Thermomechanical Behavior of Poly(methyl methacrylate) (PMMA)

Mathiesen, Danielle Samone January 2014 (has links)
No description available.
394

Dynamic response of a shipping container rack and suspended automotive parts under random excitation: Experimental, Computational and Analytical Studies

Ramanathan, Arun Kumar Kumar 28 July 2017 (has links)
No description available.
395

Stability Analysis of Additively Manufactured Isogrid

Ananth, Sirija January 2015 (has links)
No description available.
396

The Causes of “Shear Fracture” of Dual-Phase Steels

Sung, Ji-Hyun 23 August 2010 (has links)
No description available.
397

CHARACTERIZATION AND SIMULATED ANALYSIS OF CARBON FIBER WITH NANOMATERIALS AND ADDITIVE MANUFACTURING

Oluwaseun Peter Omole (17002056) 03 January 2024 (has links)
<p dir="ltr">Due to the vast increase and versatility of Additive Manufacturing and 3D-printing, in this study, the mechanical behavior of implementing both continuous and short carbon fiber within Nylon and investigated for its effectiveness within additively manufactured prints. Here, 0.1wt% of pure nylon was combined with carbon nanotubes through both dry and heat mixing to determine the best method and used to create printable filaments. Compression, tensile and short beam shear (SBS) samples were created and tested to determine maximum deformation and were simulated using ANSYS and its ACP Pre tool. SEM imaging was used to analyze CNT integration within the nylon filament, as well as the fractography of tested samples. Experimental testing shows that compressive strength increased by 28%, and the average SBS samples increased by 8% with minimal impacts on the tensile strength. The simulated results for Nylon/CF tensile samples were compared to experimental results and showed that lower amounts of carbon fiber samples tend to have lower errors.</p>
398

Quantification of the Susceptibility to Ductility-Dip Cracking in FCC Alloys

Luther, Samuel James 29 September 2022 (has links)
No description available.
399

Fast mapping of finite element field variables between meshes with different densities and element types

Scrimieri, Daniele, Afazov, S.M., Becker, A.A., Ratchev, S.M. 04 March 2020 (has links)
Yes / In the simulation of a chain of manufacturing processes, several finite element packages can be employed and for each process or package a different mesh density or element type may be the most suitable. Therefore, there is a need for transferring finite element analysis (FEA) data among packages and mapping it between meshes. This paper presents efficient algorithms for mapping FEA data between meshes with different densities and element types. An in-core spatial index is created on the mesh from which FEA data is transferred. The index is represented by a dynamic grid partitioning the underlying space from which nodes and elements are drawn into equal-sized cells. Buckets containing references to the nodes indexed are associated with the cells in a many-to-one correspondence. Such an index makes nearest neighbour searches of nodes and elements much faster than sequential scans. An experimental evaluation of the mapping techniques using the index is conducted. The algorithms have been implemented in the open source finite element data exchange system FEDES.
400

Prozesskettensimulation als zukünftiger Standard der numerischen Berechnung

Bauer, Alexander, Robertson, Jeff 20 June 2024 (has links)
Steigende Anforderungen an die Genauigkeit und Aussagekraft numerischer Berechnungen sowie neue Werkstoffe und Prozesse erfordern zunehmend technologische Erweiterungen und Entwicklungen innerhalb der Softwarelösungen. Neben der Ausweitung von Möglichkeiten in der Material- und Prozessmodellierung sowie der genaueren Abbildung physikalischer Prozesse, stehen dabei zunehmend Prozessketten im Fokus. Die Historie, welche Halbzeuge oder Bauteile bereits vom Urformprozess an mit sich führen, bestimmt dabei zu einem erheblichen Grad die Eigenschaften und damit auch mögliche Verfahrensgrenzen in allen nachfolgenden Prozessstufen. Dadurch wird deutlich, dass eine Betrachtung ebendieser vorangegangenen Schritte einen deutlichen Einfluss auf das Bauteilverhalten in den Folgeprozessen hat, wodurch die Aussagekraft entkoppelter Simulationen ab einem bestimmten Detailgrad dahingehend begrenzt bleibt. Der damit steigenden Komplexität von Berechnungsproblemen stehen auf der anderen Seite Forderungen einer immer leichter und intuitiver werdenden Bedienung von Simulationssoftware entgegen. Hexagons Smart Shop Softwarelösungen nehmen dabei das Problem der Prozessketten- simulation von der Umformung bis zur Assemblierung in den Fokus. Neben der Berechnung und Evaluierung von komplexen metallischen Baugruppen sowie der nahtlosen Integration physischer Messtechnik, spielt dabei die Bedienbarkeit eine bedeutende Rolle. Das Ziel ist mögliche Probleme in der Produktentwicklung zeitnah zu detektieren und zu adressieren, um physische Prototypen auf ein Minimum reduzieren zu können (Abbildung 1). Am Beispiel eines Karosseriebauteils erfolgt innerhalb des Beitrags die Darstellung eines Workflows zur Detektion möglicher Fertigungsprobleme in der Produktentwicklungsphase sowie die Beleuchtung weiterer Anwendungsfälle. / Increasing demands towards the accuracy and significance of numerical simulations as well as new materials and processes require technological enhancements and developments within the software solutions. Beyond extending possibilities for material- and process modeling as well as more accurate prediction of physical behavior, process chains get into the spotlight more and more. The history which parts already inherit as from the casting stage on determines the attributes and therefore also possible process limits in all following production stages. This illustrates that the analysis of this preceding process steps has a significant impact on the part behavior in all subsequent steps, which is why the meaningfulness of decoupled simulations is limited at a certain demand for detail. The increasing complexity of the simulation problems on one hand are facing demands for higher user friendliness and more intuitive control of the simulation software on the other hand. Hexagons Smart Shop software solutions have their focus on the process chain simulation from forming to assembly. Beyond the calculation and evaluation of complex metallic assemblies and the seamless integration of metrology devices, usability plays a major role. The aim hereby is to detect and address possible issue within the product development as early as possible and therefore reduce physical prototypes to a minimum. With the example of a body in white part, it is shown how a workflow for the detection of possible manufacturing challenges within the product development as well as other alternative use cases can look like.

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