1. Incorporating graphene nanoplatelets and carbon nanotubes in biobased Ppoly(ethylene 2,5-furandicarboxylate): Fillers’ effect on the matrix’s structure and lifetimeDimitra Kourtidou, Dimitrios Karfaridis, Thomas Kehagias, George Vourlias, Dimitrios Bikiaris, Konstantinos Chrissafis, 2023, original scientific article Keywords: polymer nanocomposites, poly(ethylene 2, 5-furandicarboxylate) (PEF), carbon nanofillers, structural analysis, lifetime predictions Published in DKUM: 10.04.2024; Views: 196; Downloads: 11
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2. GO-enabled bacterial cellulose membranes by multistep, in situ loading : effect of bacterial strain and loading pattern on nanocomposite propertiesTobiasz Gabryś, Beata Fryczkowska, Urška Jančič, Janja Trček, Selestina Gorgieva, 2023, original scientific article Abstract: This paper presents the results of research on the preparation and properties of GO/BC nanocomposite from bacterial cellulose (BC) modified with graphene oxide (GO) using the in situ method. Two bacterial strains were used for the biosynthesis of the BC: Komagataeibacter intermedius LMG 18909 and Komagataeibacter sucrofermentans LMG 18788. A simple biosynthesis method was developed, where GO water dispersion was added to reinforced acetic acid-ethanol (RAE) medium at concentrations of 10 ppm, 25 ppm, and 50 ppm at 24 h and 48 h intervals. As a result, a GO/BC nanocomposite membrane was obtained, characterized by tensile strength greater by 150% as compared with the pure BC (̴ 50 MPa) and lower volume resistivity of ~4 ∙ 109 Ω × cm. Moreover, GO addition increases membrane thickness up to ~10% and affects higher mass production, especially with low GO concentration. All of this may indicate the possibility of using GO/BC membranes in fuel cell applications. Keywords: bacterial cellulose, graphene oxide, nanocomposite, structural analysis Published in DKUM: 13.03.2024; Views: 341; Downloads: 13
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3. Numerical analysis of a wind turbine blade with different softwareGorazd Hren, 2019, original scientific article Abstract: The development of wind power generation technology recognises the wind turbine blade design and manufacturing as crucial for its performance. The laboratory size wind turbine blade was analysed, considering the 3D printing plastic material for blades. Applying the structural dynamic equations of blades, the aero-elastic model of the rotating rotor and the numerical simulation method of the deflections are presented under the aerodynamic loads and centrifugal forces. Based on the parameters of aerofoil and the geometrical parameters of blade, 3D model of the blade was established with the modelling software. Then the model was introduced into computational flow dynamics software to carry out the loads on the blade and further into numerical structural analysis. The analysis was performed in two different software packages. Design of wind turbine blades depends on high precision, reliable and robust numerical predictions of performance where the plug-in software is found to be inadequate for nontrivial problems. Keywords: computational fluid dynamics, numerical analysis, structural analysis, wind turbine blade Published in DKUM: 22.02.2024; Views: 332; Downloads: 49
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4. PET film production : a report for AMPEF - EUROPE (Association of Manufacturers of Polyester Films), Brussels, January 1998Ian Boustead, 1998, technical report Keywords: polymers, polyethylene terephthalate, structural analysis, structure, ethylene, PET, commercial policy, production, system examined, ecology, presentation, profiles, results, tables, methodology, energy Published in DKUM: 01.06.2012; Views: 2002; Downloads: 57
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5. Application of the european SINTAP procedure to the failure analysis of a broken forkliftNenad Gubeljak, Uwe Zerbst, Jožef Predan, Maks Oblak, 2004, original scientific article Abstract: The recently developed European flaw assessment procedure SINTAP was applied to the failure analysis of a broken fork of a forklift. Based on the service load at failure, critical crack sizes were determined at different analysis levels of the procedure. It was shown in the present case study that the failure was caused by defective design. Keywords: structural integrity, mechanics of structures, forklift, fracture mechanics, critical crack size, failure analysis, SINTAP procedure, load bearing capacity Published in DKUM: 01.06.2012; Views: 2294; Downloads: 95
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6. The re-characterisation of complex defectsBoštjan Bezenšek, John. W. Hancock, 2004, original scientific article Abstract: The re-characterisation of complex defects with re-entrant sectors has been addressed for cracks extending by fatigue, ductile tearing and cleavage. In Part I crack extension by fatigue and ductile tearing was discussed. In Part II cleavage data are presented for a family of complex defects with re-entrantsectors. Experimental tests on complex and re-characterised profilesare analysed using deterministic and probabilistic approaches. The work addresses the conservatism of re-characterisation procedures when appliedto cleavage failure on the lower shelf and in the ductile-brittle transition. Keywords: fracture mechanics, structural elements, complex defects, recharacterisation, line-spring analysis, cleavage failure, constraint, statistical fracture mechanics, numerical analysis Published in DKUM: 01.06.2012; Views: 1461; Downloads: 101
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7. The re-characterisation of complex defectsBoštjan Bezenšek, John. W. Hancock, 2004, original scientific article Abstract: Defect assessment codes idealise complex defects as simple shapes which are amenable to analysis in a process known as re-characterisation. The present work examines the re-characterisation of complex defects which extend by fatigue, ductile tearing or cleavage. A family of representative defects were analysed numerically, while a related experimental programme investigated defect interaction and failure. Part I of the paper focuses on fatigue and ductile tearing. Part II examines cleavage. The numerical and experimental results are discussed within the context of the re-characterisation proceduresdescribed in BS 7910 (Guidance on methods for assessing the acceptability of flaws in metallic structures. London, UK: British Standard Institution; 1999 [Chapter 7] and R6/4 (Assessment of the integrity of structures containing defects. Gloucester: British Energy Generation Ltd.; 2001 [Revision 4, Chapters I and II.3]). The level of conservatism of the re-characterisation prpcedures for fatigue and ductile tearing are discussed. A possible non-conservatism of the re-characterisation for cleavage is discussed in Part II, within the framework of constraint based statistical fracture mechanics. Keywords: fracture mechanics, structural elements, complex defects, recharacterisation, line-spring analysis, fatigue, ductile tearing, cracks, numerical analysis Published in DKUM: 01.06.2012; Views: 1647; Downloads: 104
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8. Intelligent FEA-based design improvementMarina Novak, Bojan Dolšak, 2008, original scientific article Abstract: Structural analysis using the finite element method is an integrate part of the design process for many components. Finite element analysis is the most extensively used numerical analysis in mechanical engineering practice and is incorporated into many computer-aided design systems. The existing commercial software is very helpful when supporting realisation of the analysis process but still fails to provide adequate support during the post-processing phase. The results of analysis should be studied and decisions made regarding the designćs suitability with respect to its engineering specifications. In general, design changes are indispensable and designers need help to design them properly. The prototype of an intelligent rule-based consultative system is being developed by the authors to provide such advice when considering a description of the design structurećs critical area. This system is encoded in Prolog. It can deal with the results of prior strain-stress or thermal analysis. It presents a short list of proposed design changes that should be taken into account when improving the design. Keywords: structural analysis, finite elment analysis, design modification, decision support, Prolog, knowledge-base systems Published in DKUM: 31.05.2012; Views: 2088; Downloads: 84
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