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Přestavba zavěšení předních kol automobilu / Conversion of Car Front SuspensionChaura, Václav January 2019 (has links)
This diploma thesis is focused on the design of the conversion of the car front suspension for racing purpose. Existing suspension solution is described by analyse static and kinematic quantities. Furthermore, a change of suspension is proposed to improve the driving characteristics of the vehicle, where the kinematic, dynamic and strength analysis of the newly designed suspension is performed. The conclusion summarizes the comparison of the original and the new suspension design.
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Výkonový měnič pro svařování elektrickým obloukem / Power Converter for the electric arc weldingJaša, Jakub January 2014 (has links)
This thesis deals with the peripheral design, construction design and implementation welder DC arc. The concept of welder is based on the use of two single action forward converter working-pull. Converters operate at a frequency of 60 kHz. Output current can be adjusted in the range from 0 to 140 A. After switching function the welder can operate as a battery charger. Charging current can be adjusted in the range of 0-70 A. The device is powered from a single phase supply 230 V.
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Měnič pro umělou síť 230 V napájený z fotovoltaických panelů / 230 V inverter for isolated mains supplied from solar cellsMichálek, Pavel January 2016 (has links)
In this thesis is presented detail design of power part of DC/DC converter and output inverter. This device will serve for creating an artificial network in a family house where it will be used for supplying selected household appliances which are designed for use in AC network. The converter will be supplied with DC voltage. This tension will be obtained from a system of photovoltaic panels. The output voltage will have alternate character and it will be close to the network voltage 230 V/50 Hz. In the introductory part of thesis are discussed possible topologies of converters and output inverters. Subsequently are designed individual parts of supply inverter. In the final part there are shown waveforms of important values and is given a thesis evaluation.
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Characterization and Simulation of Material Distribution and Fiber Orientation in Sandwich Injection Molded PartsPatcharaphun, Somjate 29 September 2006 (has links)
In this work, the material distribution, structure of fiber orientation and fiber attrition in
sandwich and push-pull injection molded short fiber composites are investigated, regarding the
effect of fiber content and processing parameters, given its direct relevance to mechanical
properties. The prediction of the tensile strength of conventional, sandwich and push-pull
injection molded short fiber composites are derived by an analytical method of modified rule of
mixtures as a function of the area fraction between skin and core layers. The effects of fiber
length and fiber orientation on the tensile strength are studied in detail. Modeling of the
specialized injection molding processes have been developed and performed with the simulation
program in order to predict the material distribution and the fiber orientation state. The secondorder
orientation tensor (a11) approach is used to describe and calculate the local fiber
orientation state. The accuracy of the model prediction is verified by comparing with
corresponding experimental measurements to gain a further basic understanding of the melt flow
induced fiber orientation during sandwich and push-pull injection molding processes.
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Lösbare Verbindungstechnik für Bauteile aus Wood Polymer Composite (WPC) unter dynamischen BelastungenSchubert, Christine, Schleinitz, Armin, Kluge, Patrick, Eichhorn, Sven 21 August 2018 (has links)
Im Projekt wurden lösbare Verbindungstechniken für hochgefüllte Holz-Polymer-Werkstoffe für das statisch-dynamische Belastungskollektiv des Maschinenbaus erarbeitet. Im Fokus der Untersuchungen standen vorgespannte Schraubverbindungen in den konstruktiven Ausführungen als Durchsteckschraubverbindung und Einschraubverbindungen. Die Direktverschraubung und die Quergewindebolzen-Steckschraubverbindung wurden aus technisch-wirtschaftlicher Sicht für den Werkstoff als Sonderverfahren der Einschraubverbindung favorisiert. Für die benannten Verschraubungsarten wurden Montageempfehlungen, Grenzlastbereiche und Einflussfaktoren der Verbindungen unter Berücksichtigung des Werkstoffes erarbeitet.
Abschließend wurden die erarbeiteten Kenntnisse zu lösbaren Verbindungstechniken auf einen Demonstrator in der Fördertechnik übertragen. / In the project removable connection methods for high filled wood polymer composites for static and dynamic loads were worked out.
The focuses of studies were pre-stressed screw connections in a constructive style as push-through screw connection and screw in connection. On the basis of the material and the technical-economic reasons the 'direct-screw-connection' and 'cross-threaded bolt plug-in screw connection' were favored as a special method of the screw-in connection. Installation recommendations, limit load ranges and influencing factors of the connections based on the material were compiled for the named types of bolting.
Finally the compiled knowledges of the removable connections were transferred into demonstrator for conveying systems.
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Secure Bitcoin WalletGuler, Sevil January 2015 (has links)
Virtual currencies and mobile banking are technology advancements that are receiving increased attention in the global community because of their accessibility, convenience and speed. However, this popularity comes with growing security concerns, like increasing frequency of identity theft, leading to bigger problems which put user anonymity at risk. One possible solution for these problems is using cryptography to enhance security of Bitcoin or other decentralised digital currency systems and to decrease frequency of attacks on either communication channels or system storage. This report outlines various methods and solutions targeting these issues and aims to understand their effectiveness. It also describes Secure Bitcoin Wallet, standard Bitcoin transactions client, enhanced with various security features and services.
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Exploring the attraction of nurses to a managed care organizationStraulino, Patrizia 27 January 2014 (has links)
The main aim of this research study was to explore attraction factors pertaining to the literature and to the occupational context of nursing personnel who have exhibited employment interest in a managed care organisation. A qualitative research approach was adopted in which semi-structured interviews were held to collect rich exploratory data from the purposeful sample of nine applicants with nursing qualifications.
Twenty-five themes were identified through interpretive data analysis as being important factors in the pre-interview attraction process. The highest ranking of these were identified to be opportunities for professional and personal growth and the relationship with the managed care client, followed by salary and working hours. This study contributes knowledge to Personnel and Career Psychology in the field of Industrial and Organisational Psychology and is pertinent to organisations recruiting nurses, advising them in the formulation of contextually appropriate attraction strategies that attend to the most notable attraction factors / Industrial and Organisational Psychology / M.Com. (Industrial and Organizational Psychology)
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Energy Policies and Directed Technical Change : How Governments Incentivize Firms to Invests in Renewable Energy innovation / Energipolitik och riktad teknologisk utveckling : Hur Regeringar ger incitament till företag att investera i förnyelsebar energi-innovationRoberts, Christopher January 2019 (has links)
Policies are regarded as the most important instrument in redirecting invention Policies are regarded as the most important instrument in redirecting invention investments away from fossil fuel technologies towards renewable energy technologies. Despite the importance and urgency in decarbonizing the economy, the literature on how different energy policies effect the development of renewable energy technologies is relatively scarce. A difficulty has been in justifying the operationalizing of policies in as both valid and reliable. This thesis tackles the operationalization difficulty and produces empirical evidence in how effective various policies are in incentivizing the development of renewable energy technologies (RET). The main findings are that government R&D expenditure increases firm innovation across all RET, demand-pull policies either increase the likelihood of firm inventions or has an insignificant effect and carbon taxation does not increase the likelihood of RET invention. / Politiska instrument är ansedda som de medel som kan ha störst inverkan att omdirigera innovation investeringar från fossila till förnyelsebara energier. Trots det angelägna och brådskande i att ekonomin blir fossilt oberoende finns det relativt lite litteratur på hur olika energipolitiska medel har för effekt på den tekniska utvecklingen av förnyelsebara energier. En svårighet har varit att berättiga operativiseringen av politiken vilken är både valid och tillförlitligt. Denna uppsats angriper svårigheten av att operativisera poliska instrument och producerar empiriska underlag för hur effektiva olika politiska medel är i att ge incitament till för att utveckla förnyelsebara energier (FE). De frästa resultaten är att statlig forskning och utveckling ökar sannolikheten att företags innovation inom alla FE, efterfråge-stimulerings politik antingen ökar eller har ingen påverkan på FE innovation och att koldioxidbeskattning inte ökar innovation inom FE.
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Innovation in Business to Business Payment Services: a contextual approach to future innovationJackson, David January 2018 (has links)
Payments take place every day in exchange for goods and services. There are a large variety of different methods which can be used to make a payment, and multiple scenarios in which payments take place. Recently there has been a significant amount of innovation in the Payment Services sector, however the majority of this innovation has occurred in the Business-to-Consumer (B2C) market, leaving the Business-to-Business (B2B) market relatively devoid of innovations. This raises the question, why are there limited successful innovations in B2B Payment Services? Furthermore, are there areas for innovation in the realm of B2B Payments? To explore this perceived gap in innovation, the payment methods available to small B2B companies were examined to identify key challenges and areas for future innovation in B2B payments. The research contains primary data from semi-structured telephone interviews with five owners or managers in SME (Small or Medium-Sized Enterprise) B2B companies, located in the United Kingdom. It will be concluded that the payment methods available to small businesses are sufficient for their needs, and there were no real ‘pain points’ with the actual payments themselves – and this is posited as one reason why payment services innovation has been limited within B2Bs. However, each business experienced a number of challenges in the bigger-picture payment cycle and business purchasing flow. It is within this space - helping businesses manage payments, not make payments - that opportunities for innovation lie, and a conceptualisation of new business opportunities is discussed. / <p>Master of Entrepeneurship and Innovation Management (TEILM)</p>
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Industrial steel storage racks subjected to static and seismic actions: an experimental and numerical studyBernardi, Martina 16 November 2021 (has links)
Industrial steel storage racks are pre-engineered lightweight structures commonly used to store goods from supermarkets to big warehouses. These systems are framed structures, usually made of cold-formed steel profiles and characterised by non-standard details. Their performance is quite complex and the prediction of their global response is more difficult than for the traditional steel frames. This difficulty is due to the racks’ main features: the use of cold-formed thin-walled steel sections which are sensitive to different buckling modes, the presence of regular perforation patterns on the uprights, the highly non-linear behaviour of joints, the influence of the structural imperfections and the significant frame sensitivity to second order effects. The behaviour of racks becomes even more complex when seismic or accidental events induce significant horizontal forces acting on the structures. The complexity and variability that characterise racks make it difficult to identify general design solutions. Hence, racks design is traditionally carried out by using the “design by testing” approach, which requires the experimental characterisation of the main structural components, of the joints and the sub-assemblies. The complexity of the racks also affects their numerical modelling, which results in complex analyses that must take into account all the aforementioned features. The work presented in this thesis focuses on the study of a typical steel pallet rack, identified as case study. The research aims to contribute to building up a comprehensive knowledge of the response of both the main rack components and of the whole structure. The main rack components were first individually studied. The behaviour of the uprights, of the base-plate joints and of the beam-to-column joints was experimentally investigated. The experimental data were then taken as reference for the calibration of FE models that enabled exploring each component’s performance. These models were then incorporated into the whole rack model. The response of the uprights was first investigated through stub column tests. The non-negligible interaction between axial force and bending moment of the upright response was then experimentally and numerically analysed to define the M-N domains. In addition, the rules provided by different European standards for the design of isolated members subjected to combined axial load and bending moment were considered and critically compared, identifying the main critical issues of the different design approaches. Although the contribution of joints on the rack global response is of paramount importance, to date, the knowledge is quite limited. In particular, the experimental studies of the behaviour of base-plate joints are still rather modest, especially for the cyclic range. Therefore, an experimental campaign on the rack base-plate joints was carried out: three levels of axial load were considered and the response in both the down-aisle and the cross-aisle direction was investigated under monotonic and cyclic loadings. Similarly, the beam-to-column joint was tested both monotonically and cyclically, taking into account its non-symmetric behaviour. Numerical models for both joint types were developed and validated enabling the characterisation of joints in the monotonic and cyclic range. This in-depth knowledge of the response of individual components facilitated the evaluation of the global rack behaviour. As a final stage of the research, full-scale tests of four-level two-bay racks were performed taking advantage of an innovative full-scale testing set-up and, on the basis of the experimental outcomes, the racks’ global behaviour was numerically investigated. Critical standards issues and needs for future research were further identified.
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