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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.
21

A comparative study of 2 CAD-integrated FE-programs using the linear static analysis

Amin, Handren January 2009 (has links)
This Master’s thesis is summery of a comparative study of 2 commercial CAD-integrated FE-programs. These FE-programs were CATIA v5 and ABAQUS 6.3-7. The primary objective of this study is to investigate the basic FEA capabilities of CATIA and ABAQUS 6.7-3 in performing the linear static analysis and to identify whether there are any differences and similarities between results the both Finite Element FE codes give. The overall research question in the present thesis is: Do different FE programs, here CATIA and ABAQUS, give the same results for FE analysis giving the same models if subjected to the same boundary conditions? This research seeks to achieve its aims through making a comparative qualitative study. Certain pre-selections were performed in advance of conducting Finite element analysis and the comparison process to ensure that results would reflect only the most relevant and meaningful differences and similarities between the both FE-codes. Five different 3D solid models have been selected to perform linear static Finite element analysis on. All these models (case studies) are created in CATIA V5 and the linear static analysis conducted on using FE-codes CATIA v5 and ABAQUS 6.7-3. Three static responses (results) of the linear static analysis have been adopted as criteria for comparisons purposes. These criteria were: (1) displacements, (2) Von Mises stress, and (3) principal stress. The results of comparisons showed that there is a very good agreement in most cases and small gap between in a few cases. Results of this study demonstrate that the both FE-programs CATIA v5 and ABAQUS 6.7-3 have good capabilities to perform FE-analysis and they give very near results. Reason behind differences is that each of them uses a different algorithm for solving problems. The final answer for the research question is given with valuable recommendations for future work in the scope of this research.
22

A general computer-based methodology for work injury analysis in a production assembly line

Emodi, Chukwumobi Tagbo 01 May 2007 (has links)
Repetitive injuries have been a major obstacle in production assembly lines all over the world. These injuries have greatly reduced the production efficiency of assembly plants and also negatively affected human health. Various attempts have been made by the Canadian government through the Workers Compensation Board (WCB) to prevent the occurrences of these injuries because of the associated cost and effects. These attempts failed as the cost of injuries acquired in the workplace continues to increase. For example, in New Zealand alone, the total cost of accidents in 2005, is estimated at $300 million (Accident Compensation Corporation, 2005). In Canada, the number of accepted claims alone amount to 15623 people (Workers Compensation Board of Canada, 2003).<p>A human body can be viewed as a mechanism that is composed of links and joints controlled by a central nervous system and are subject to stress, strain, fatigue and failure as can be observed on a regular industrial robot. But unlike the robot which is designed proactively, these stress and strain factors could be because of certain conditions such as inappropriate work posture, poor assembly line design, excessive workload, and poor work conditions. <p>Often, it is almost uncertain to make a conceptual assessment of the appropriate ergonomic design of a production system before the assembly line is built and put in use. This research will propose a general computer-based methodology for analysis of work injuries given an assembly line where human workers perform repetitive operations. The general methodology integrates sophisticated computer software systems for biomechanics simulation with various manual measurement techniques and methods. The research further proposed a simple and handy synthesis method with which problematic areas of assembly line design, with special reference to human work design can be identified and improved. The proposed methodology for analysis and synthesis is then implemented in a real assembly line to understand the effects of different work activities on the human body. Various software packages and motion tracking techniques will be considered prior to the actual implementation of the final methodology. A rule of thumb table will also be presented as a guideline for the re-design process. The research also proposed a general procedure and specific formula within a specific regional context to calculate the costs of worker injuries in real-life assembly system. This formula thus allows us to obtain the total cost of injuries in a production assembly line, making it possible to optimize the design and operation of the assembly line.
23

Automatisierte Ermittlung bauteilspezifischer Kennwerte in komplexen Produktstrukturen zur Abstraktion umfangreicher Gesamtbaugruppen im Textilmaschinenbereich

Kurth, Robin 01 July 2015 (has links) (PDF)
Steigende Komplexität von Maschinen und Anlagen sowie unternehmensindividuelle Produktstrukturen führen zu Herausforderungen im Handling großer 3D-Modelle in kommerziell verfügbaren CAD-Systemen. Der Vortrag thematisiert die Anwendung unterschiedlicher Automatisierungsmöglichkeiten des CAD-Systems CATIA V5® der Firma Dassault Systèmes. Hierbei wird zum einen auf die besonderen Herausforderungen im Konstruktionsbereich des Textilmaschinenbaus eingegangen. Zum anderen werden Vorschläge für eine parametergesteuerte Anlagenkonzeption auf Basis von Knowledgeware, eine automatisierte Abstraktion großer Baugruppen und für die automatisierte Ermittlung masseabhängiger Parameter komplexer Produkte vorgestellt.
24

Knowledge-Based Flight Control System Integration in RAPID

Escolano Andrés, Inés January 2015 (has links)
This thesis work presents a parametrized integration of the flight control system within RAPID by means of the automation in CATIA V5, using Knowledge Pattern. Nowadays aircraft’s design and development processes are not only time-consuming but also incur high economic cost. In addition, system integration is highly a multi-disciplinary design process which often involves a large number of different discipline teams working at the same time and space. The main objective of this thesis is to investigate how CAD (Computer Aided Design) software can be used in the early design stages to define the flight control system integration. The purpose of this work to improve the functionality of an in house produced aircraft conceptual design tool carried out at the Division of Fluid and Mechatronic Systems, Linköping University. The work consists of preliminary integration of the RAPID flight control system and the hydraulics associated to it. By defining several reusable templates, the automatic definition of a flight control system within the RAPID aircraft has been achieved. Moreover it is a parametrical model which allows the user to modify a high number of features as desired to enhance the design process. For this, a user interface in Microsoft Excel connected to CATIA has also been attained.
25

The problem of evil : with special reference to P.T. Forsyth, John Wisdom and Ludwig Wittgenstein

Vicchio, Stephen J. January 1986 (has links)
Chapter one begins with a definition and exposition of the concept of theodicy, and a topology for characterizing comparative theodicies is suggested. It is argued that the basis on which theodicies might be compared is the foundational ontological principles on which they are built. Chapter two is a lengthy discussion regarding the meaning of terms such as omnipotence omniscience omnibenevolence, moral evil and natural evil. Chapter three begins with a critical analysis of a variety of theodicies found throughout the history of Christian theology. The final conclusion drawn in this chapter is that none of the proposed answers is acceptable. Acceptability is measured in three important ways: First, is the position logically consistent, second, does it conform, at least in a broad way, to the major tenents of the Christian form of life, and third, does this position take the individual sufferer seriously? In chapter four a foundation is laid for a response to the problem of evil which is to follow in chapter five. In this penultimate chapter an analysis of the Book of Job is offered which centers on the interpretation of Yahweh's speeches out of the whirlwind. It is suggested that the crux of Jobs repentance is to be understood in connection with Job "seeing God." In chapter five, an attempt is made, using the help of Karl Barth, D. M. Mackinnon, P. T. Forsyth, Ludwig Wittgenstein and John Wisdom, as well as some insights gained from chapter four, to argue that there is a teleological response to the problem of evil that is logically consistent, true to the Christian form of life and sensitive to the needs of the individual sufferer.
26

Metodjämförelse för fixturkonstruktion till prototyptillverkning

Aldegård, Alexander, Gapinski, William January 2018 (has links)
The thesis work is done in collaboration with Prodtex AB, which works to develop digital tools to facilitate the constructor´s work in virtual environments, for instance CAFD within CATIA V5. What the client wanted the project participants to perform was a comparison of the company's semi-automatic software for fixture design, and the traditional construction method with CATIA. The reason for the method comparison is because Prodtex AB requires data, which they can present to potential customers. The participants produced a method to enable the necessary components of the project, the method consisted of training in fixture design, fixture construction and work with the consulting company´s application. These elements have been essential for the comparison to be reliable. The main part of the assignment consisted of constructing units for the given fixture. The reason behind this is due to the necessity of a certain level of experience in fixture design, which is required to be able to assemble units with an accurate and efficient procedure. The method comparison generated data in terms of time in the measurement areas, input, design and export that the project participants analyzed and compiled in the result section. Based on the statistics, participants were able to find answers about which features the software made the most time savings of, and how abundant these were in relation to the traditional design method. A conclusion about when it was beneficial for a company to invest in the software was based on reasoning deduced from the outcome discussion.
27

Konstruktion av svingarm till EcoistVehicleTM

Öhman, Oliver, Wikman, Christian January 2017 (has links)
Den här rapporten handlar om ett maskintekniskt konstruktionsprojekt som framtagits av Christian Wikman och Oliver Öhman. Det är ett uppdrag som givits av EcoistVehicleTM för att slutföra högskoleingenjörsexamen inom maskinteknik vid Högskolan i Halmstad. Princip- och Primärkonstruktion (Olsson, 1995), Fundamentals of Vehicle Dynamics (Gillespie, 1992) och en stor mängd egen sökning har använts som grund till metoden som använts under projektets gång.   EcoistVehicleTM är ett fordonsprojekt som startats av Thomas Koch. Det är en eldriven, singelsits och trehjulig bil med ett drivande bakhjul. Idén bakom bilen är att transportera föraren till sin destination på ett miljövänligt sätt. Bilen är lämpad till landsbygd och pendling med en räckvidd på 40-50km. Syftet med uppdraget som gavs våren 2017 var att hitta snabbare metoder att konstruera och tillverka en svingarm till fordonet.   Uppdraget som gavs var att konstruera och möjligtvis tillverka en svingarm för det drivande bakhjulet som skall passa in på bilens dimensioner samt ha en relativt snabb tillverkningsprocess för en produktionsserie på 10-20 bilar. Uppdragsgivarens önskemål var att 3D-printa ut de större delarna av svingarmen och sedan efterbearbeta monteringsdelar och passytor med fräsning. Flera tillverkningsprocesser som används inom fordonsindustrin för framtagning av motorcykelsvingarmar har setts över och jämföras för att få fram den metod som passar detta projekt.   Det som författarna bidragit med till projeketet är en högre kunskap om 3D-printning av metall, då specifikt aluminium, olika koncept för tillverkning samt analyser av konstruktionen för att testa hållfasthet till den slutgiltiga produkten. / This report will be about a mechanical design project that has been developed by Christian Wikman and Oliver Öhman. The assignment was given by EcoistVehicleTM to complete a bachelor’s degree in mechanical engineering at Halmstad University. Princip- och Primärkonstruktion (Olsson, 1995), Fundamentals of Vehicle Dynamics (Gillespie, 1992) and a large amount of research on the web has been used as the foundation for the method that’s been used all through this project.   EcoistVehicleTM is a vehicle project started by Thomas Koch. It is an electrically powered, single seat, three wheeled vehicle that's driven by a single rear wheel. The idea behind the car is to transport the driver to his destination in an environmentally friendly way. The car is suited for commuting in the countryside with a range of 40-50km. The purpose of the assignment that was given in the spring of 2017 was to look into faster methods of designing and manufacturing a swingarm for the vehicle.   Our assignment was to design and possibly manufacture a swingarm for the driving rear wheel that should fit the specifications of the car and have a relatively fast manufacturing process for a series of 10-20 cars. Our mentor and taskmaster has a request to 3D-print the larger parts of the swingarm then after work the mounting surfaces and mating surfaces with milling. Several manufacturing processes used in the automotive industry for the production of motorcycle swingarms will be screened and compared to get the method that will fit this project.   The authors have contributed with a higher knowledge of 3D-printing, specifically aluminum, different design concepts together with analysis of the design to test the solidity of the final product.
28

Ergonomie pracoviště malého výrobního podniku / Ergonomics of a small manufacturing company

Vršková, Markéta January 2021 (has links)
The diploma thesis is focused on the ergonomic analysis of selected workplaces in the company TRUNN, s.r.o. The theoretical part of the thesis contains a summary of basic knowledge in the field of ergonomics, which are then applied in the practical part of the thesis. The practical part of the work includes a description of the current state of workplaces and evaluation of jobs using the methods described in the theoretical part. Based on the evaluation, own recommendations and suggestions are made on how to adjust the jobs. The aim of the diploma thesis is to provide workers with a suitable workplace that meets ergonomic requirements.
29

Konstruktionsoptimering av teknisk utrustning

Svensson, Robert, Rydberg, Simon January 2021 (has links)
Detta examensarbete handlar om konstruktionsoptimering av en ny och innovativteknisk produkt som riskerar att skadas då användaren av misstag tapparprodukten. Arbetet belyser tidigare studier där dropptester utförts för att insamlakunskap inför viktiga moment i detta arbete. Dropptest av produkten genomfördesoch data samlades in med hjälp av accelerometer och höghastighetskamera.Insamlad data presenteras i olika grafer och beräkningar som beskriversammanstötningsförloppet. Lösningsförslag genereras med CAD programmetCatia V5, sedan simulerades lösningsförslagen i programmet abaqus/explicit eftersamma principer och förhållanden som utfört dropptest visade. Genomfördasimuleringar verifierades med hjälp av insamlad data. Projektgruppen presenterarolika koncept av lösningsförslag till företag X genom olika exempel påkonstruktiva lösningar eller förslag till byte av befintligt produktmaterial. Underprojektets gång uppstod en del svårigheter i de olika delarna av studien, dessadiskuterades i studiens resultat- och metoddiskussion. Avslutningsvis taskonstruktionsoptimeringens inverkan på sociala, ekonomiska och miljömässigaaspekter i anseende. / This thesis is about design optimization of a new and innovative technical productthat risks being damaged when the user accidentally drops the product. The workillustrates previous studies where drop tests have been performed to gatherknowledge before introducing important stages in this work. Droptesting of theproduct was performed and data were collected using an accelerometer and ahigh-speed camera. Collected data are presented in various graphs andcalculations that describes the stages of impact. Solution proposals were generatedwith the CAD program Catia V5, then the solution proposals were transferred tothe program abaqus/explicit were the same principles and conditions that occurredduring the droptest was implemented in the simulations. Completed simulationswere verified using collected data. The project group presents different concepts iiof solution proposals to company X through various examples of constructivesolutions or proposals for replacement of existing product material. During theproject, some difficulties arose in the various parts of the study, these werediscussed in the study's results and method discussion. Finally, the impact ofdesign optimization on social, economic and environmental aspects was taken intoaccount.
30

EXPRESSION OF THE THREE PROTO-ONCOGENES, EGFR, MEK AND B-RAF AFTER TRANSFECTION INTO HUMAN CELLS AND THEIR DETECTION BY MASS SPECTROMETRY

Olum, Jimmy January 2016 (has links)
When activated by growth factors and mitogens, cellular receptors like EGFR become activated and transmit signals from the cell surface through the MAPK pathway into the nucleus of the cell, in order to elicit a cellular response like growth, apoptosis, proliferation, and survival. Over activation of EGFR even without receptor binding and members of the MAPK pathways like BRAF and MEK1 have been reported in tumorigenesis. We used Gateway Technology to study the recombinant protein expressions from these 3 proto-oncogenes in HEK293T and HeLa cell lines, using pLenti 6.3/V5 as the expression system. BRAF was neither detected in the HeLa nor in the HEK 293T cell lines, by mass spectrometry after transfection. Only in the HeLa cell line was EGFR identified meanwhile MEK1 was identified both in HEK293T and HeLa cell lines. However, the results showed that the proteins identified were endogenous to these cell lines and therefore, no recombinant proteins were expressed using the pLenti 6.3/V5, as the expression system.

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