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Wavelet Analysis for the Extraction of Morphological Features for Orthopaedic Bearing Surfaces (Book chapter)

Book title: Progress in Molecular and Environmental Bioengineering - From Analysis and Modeling to Technology Applications

Authors: --- ---
ISBN: 9789533072685 Year: DOI: 10.5772/20728 Language: English
Publisher: IntechOpen Grant: FP7 Ideas: European Research Council - 228117
Subject: Science (General)
Added to DOAB on : 2019-01-17 11:47:58
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Surface texture is one of the most critical factors and important functionality indicators in the performance of high precision and nanoscale devices and components. The functions&#xD;&#xD;that have been identified in various studies include wear, friction, lubrication, corrosion,&#xD;&#xD;fatigue, coating, paintability, etc. [1-3]. It is also reported that the wear rates of surfaces in&#xD;&#xD;operational service is determined by roughness, waviness and the multi-scalar topographic&#xD;&#xD;features of a surface, such as random peaks/pits and ridges/valleys. These functional&#xD;&#xD;topographical features will impact directly on wear mechanics and physical properties of a&#xD;&#xD;whole system, such as hip joint replacement system in bioengineering [4-9]. For example,&#xD;&#xD;during functional operation of interacting surfaces, peaks and ridges will act as sites of high&#xD;&#xD;contact stresses and abrasion; consequently wear particles and debris will be generated by&#xD;&#xD;such surface topographical features, whereas the pits and valleys will affect the lubrication&#xD;&#xD;and fluid retention properties. In this situation, a vitally important consideration for&#xD;&#xD;functional characterisation must be the appropriate separation of the different components&#xD;&#xD;of surfaces, which is not only to extract roughness, waviness and form error, but should also&#xD;&#xD;be extended to all multi-scalar topographical events over surfaces.

Über den Zusammenhang von Tragfähigkeitsmessergebnissen mit mechanischen Modellgrößen bei Asphaltstraßen

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Book Series: Veröffentlichungen des Institutes für Straßen- und Eisenbahnwesen ISSN: 0344970X ISBN: 9783731502692 Year: Volume: 60 Pages: XV, 175 p. DOI: 10.5445/KSP/1000043258 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: General and Civil Engineering
Added to DOAB on : 2019-07-30 20:01:58
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This work examines the mechanical deformation of flexible pavement under vertical load. Mechanical approaches for the computation of the radius of curvature R0 at the centre of the loaded area from HWD data were developed. Material parameter have been backcalculated in an iterative way using rheological models After that the radius of curvature has been subsequently calculated based on mechanical systems.

100 Years of Prandtl's Wedge

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ISBN: 9781614998495 9781614998501 Year: Pages: 144 DOI: 10.3233/978-1-61499-850-1-i Language: English
Publisher: IOS Press
Subject: General and Civil Engineering
Added to DOAB on : 2018-06-20 15:09:53
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The biggest problem for a shallow foundation, just as for any other type of foundation, is a failure due to an overestimation of the bearing capacity. This means that the correct prediction of the bearing capacity of the foundation is often the most important part of the design of a civil structure. That is why the publication by Prandtl in 1920 about the hardness of a plastic body, was a major step in solving the bearing capacity of shallow foundations, although it is well possible that he never realised this, because his solution was not made for civil engineering purposes, but for mechanical purposes. Over the last 100 years, a lot of extensions have been made, for example with inclination factors and shape factors. Also many laboratory experiments have been done and numerical calculations have been made. Some even try to extrapolate the failure mechanism for shallow foundations to the failure mechanism around the tip of a pile. All this scientific work leads back to the first publication by Ludwig Prandtl in 1920.This book, “100 Years of Prandtl’s Wedge”, is intended for all those who are interested in these fundamentals of foundation engineering and their history. The Appendices include a copy of Prandtl’s Über die Härte plastischer Körper and of Reissner’s publication of 1924, Zum Erddruckproblem.

Modeling and simulation of porous journal bearings in multibody systems

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Book Series: Schriftenreihe des Instituts für Technische Mechanik, Karlsruher Institut für Technologie ISSN: 16143914 ISBN: 9783731500841 Year: Volume: 21 Pages: XXII, 144 p. DOI: 10.5445/KSP/1000036099 Language: ENGLISH
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:01:59
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A specific cost-efficient type of plain journal bearing is the porous journal bearing, which possesses a pervious bush that serves as a lubricant reservoir. The current work is concerned with modeling porous journal bearings in multibody systems, for which dynamical models are needed to investigate the bearing&#8217;s behavior. Such porous journal bearing models as well as models of elementary rotor-bearing systems including these, were developed and investigated during the course for this work.

L’artisanat du métal à Alep : Héritage et postérité

Authors: --- ---
ISBN: 9782351595435 DOI: 10.4000/books.ifpo.11245 Language: French
Publisher: Presses de l’Ifpo
Subject: Social Sciences
Added to DOAB on : 2019-12-06 13:15:32
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Cette recherche a pris forme avec l’ambition initiale de comparer le travail du métal à Alep dans les ateliers encore en place entre 2004 et 2009, avec les mêmes activités à d’autres époques en milieu urbain. La présente publication porte essentiellement sur le volet contemporain. La métallurgie traditionnelle actuelle constitue un système d’éléments en interaction dans la ville : les auteurs croisent ici les aspects techniques (les processus de fabrication) et fonctionnels (l’organisation du travail dans l’atelier et les attitudes corporelles), avec une réflexion sur l’organisation générale de l’espace en rapport avec des considérations culturelles et sociales et avec le fonctionnement des pouvoirs urbains. Cet ouvrage s’intéresse en premier lieu à des ateliers sis dans des souks anciens : forgerons, artisans du cuivre et du bronze, étameurs. Une des questions que pose cette activité porte sur les modes d’intégration de la nouveauté aux savoir-faire et aux fonctionnements hérités, par exemple sur les attitudes du travail et le rapport au sol : travailler assis au sol, assis sur un siège, debout ? La fonderie de fer, d’acier, de fonte, plus moderne, se trouve dans des ateliers plus vastes, dans des zones d’activité officielles ou informelles en périphérie. Ces ateliers font partie d’une autre économie en développement. Le passage de la petite métallurgie traditionnelle du souk aux ateliers moyens semi‑industrialisés, bien plus qu’un déplacement géographique, ne constitue-t-il pas un changement de nature ? Les enquêtes menées par les auteurs à Alep avant 2011 ainsi que leurs photographies et illustrations, enregistrent des activités disparues dont les locaux situés près d’une ligne de front ont servi de champ de bataille et ont été pillés et détruits : leurs témoignages, présentés dans cet ouvrage, possèdent donc essentiellement une valeur patrimoniale.

Keywords

Workshop --- Working space --- Corporal bearing --- Bronze --- Copper --- Copperware --- Ductility --- Iron --- Ironwords --- Kiln --- Lathe-work --- Melting --- Mould --- Pig iron --- Recycling --- Souk

Masonry Buildings: Research and Practice

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ISBN: 9783039213733 / 9783039213740 Year: Pages: 202 DOI: 10.3390/books978-3-03921-374-0 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering --- Construction
Added to DOAB on : 2019-12-09 11:49:15
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Masonry is a construction material that has been used throughout the years as a structural or non-structural component in buildings. Masonry can be described as a composite material made up of different units and diverse types of arrangements, with or without mortar, that is used in many ancient public buildings, as well as with the latest technologies being applied in construction. Research in multiple relevant fields, as well as crossing structural with non-structural needs, is crucial for understanding the qualities of existent buildings and to develop new products and construction technologies. This book addresses and promotes the discussion related to the different topics addressing the use of masonry in the construction sciences and in practice, including theory and research, numerical approaches and technical applications in new works, and repair actions and interventions in the built environment, connecting theory and application across topics from academia to industry.

Superhydrophobic Coatings for Corrosion and Tribology

Authors: ---
ISBN: 9783039217847 / 9783039217854 Year: Pages: 166 DOI: 10.3390/books978-3-03921-785-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2020-01-07 09:08:26
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Superhydrophobic surfaces, with a water contact angle >150°, have attracted both academic and industrial interest due to their wide range of applications, such as water proofing, anti-fogging, antifouling, anti-icing, fluidic drag reduction and anti-corrosion. Currently the majority of superhydrophobic coatings are created using organic chemicals with low surface energy. However, the lack of mechanical strength and heat resistance prevents the use of these coatings in harsh environments. Quality superhydrophobic coatings developed using inorganic materials are therefore highly sought after. Ceramics are of particular interest due to their high mechanical strength, heat and corrosion resistance. Such superhydrophobic coatings have recently been successfully fabricated using a variety of ceramics and different approaches, and have shown the improved wear and tribocorrosion resistance properties. This Special Issue focuses on the recent developments in the fabrication of superhydrophobic coatings and their robustness against corrosion and wear resistance, but the original work on other properties of superhydrophobic coatings are also welcome. In particular, the topics of interest include, but are not limited to: Robust superhydrophobic coatings; Coatings with super-wettability in multifunctional applications; Wetting effects on corrosion and tribology; Hierarchical Coating for wetting and modelling.

Nanogenerators in Korea

Authors: ---
ISBN: 9783038976226 Year: Pages: 160 DOI: 10.3390/books978-3-03897-623-3 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2019-03-08 11:42:05
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Fossil fuels leaded the 21st century industrial revolution but caused some critical problems such as exhaustion of resources and global warming. Also, current power plants require too much high cost and long time for establishment and facilities to provide electricity. Thus, developing new power production systems with environmental friendliness and low-cost is critical global needs. There are some emerging energy harvesting technologies such as thermoelectric, piezoelectric, and triboelectric nanogenerators, which have great advantages on eco-friendly low-cost materials, simple fabrication, and various operating sources. Since the introduction of various energy harvesting technologies, many novel designs and applications as power suppliers and physical sensors in the world have been demonstrated based on their unique advantages. In this Special Issue, we would like to address and share basic approaches, new designs, and industrial applications related to thermoelectric, piezoelectric, and triboelectric devices which are on-going in Korea. With this Special Issue, we aim to promote fundamental understanding and to find novel ways to achieve industrial product manufacturing for energy harvesters.

Gas Flows in Microsystems

Authors: ---
ISBN: 9783039215423 / 9783039215430 Year: Pages: 220 DOI: 10.3390/books978-3-03921-543-0 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General)
Added to DOAB on : 2019-12-09 11:49:16
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The last two decades have witnessed a rapid development of microelectromechanical systems (MEMS) involving gas microflows in various technical fields. Gas microflows can, for example, be observed in microheat exchangers designed for chemical applications or for cooling of electronic components, in fluidic microactuators developed for active flow control purposes, in micronozzles used for the micropropulsion of nano and picosats, in microgas chromatographs, analyzers or separators, in vacuum generators and in Knudsen micropumps, as well as in some organs-on-a-chip, such as artificial lungs. These flows are rarefied due to the small MEMS dimensions, and the rarefaction can be increased by low-pressure conditions. The flows relate to the slip flow, transition or free molecular regimes and can involve monatomic or polyatomic gases and gas mixtures. Hydrodynamics and heat and mass transfer are strongly impacted by rarefaction effects, and temperature-driven microflows offer new opportunities for designing original MEMS for gas pumping or separation. Accordingly, this Special Issue seeks to showcase research papers, short communications, and review articles that focus on novel theoretical and numerical models or data, as well as on new experimental results and technics, for improving knowledge on heat and mass transfer in gas microflows. Papers dealing with the development of original gas MEMS are also welcome.

Keywords

pressure drop --- microchannels --- heat sinks --- slip flow --- electronic cooling --- Knudsen pump --- thermally induced flow --- gas mixtures --- direct simulation Monte Carlo (DSMC) --- microfluidic --- rarefied gas flows --- micro-scale flows --- Knudsen layer --- computational fluid dynamics (CFD) --- OpenFOAM --- Micro-Electro-Mechanical Systems (MEMS) --- Nano-Electro-Mechanical Systems (NEMS) --- backward facing step --- gaseous rarefaction effects --- fractal surface topography --- modified Reynolds equation --- aerodynamic effect --- bearing characteristics --- underexpansion --- Fanno flow --- flow choking --- compressibility --- binary gas mixing --- micro-mixer --- DSMC --- splitter --- mixing length --- control mixture composition --- preconcentrator --- microfluidics --- miniaturized gas chromatograph --- BTEX --- PID detector --- ultraviolet light-emitting diode (UV LED) --- spectrophotometry --- UV absorption --- gas sensors --- Benzene, toluene, ethylbenzene and xylene (BTEX) --- toluene --- hollow core waveguides --- capillary tubes --- gas mixing --- pulsed flow --- modular micromixer --- multi-stage micromixer --- modelling --- photoionization detector --- microfluidics --- microfabrication --- volatile organic compound (VOC) detection --- toluene --- supersonic microjets --- Pitot tube --- Knudsen pump --- thermal transpiration --- vacuum micropump --- rarefied gas flow --- kinetic theory --- microfabrication --- photolithography --- microfluidics --- resonant micro-electromechanical-systems (MEMS) --- micro-mirrors --- out-of-plane comb actuation --- fluid damping --- analytical solution --- FE analysis --- miniaturization --- gas flows in micro scale --- measurement and control --- integrated micro sensors --- advanced measurement technologies --- n/a

Microscale Surface Tension and Its Applications

Authors: ---
ISBN: 9783039215645 / 9783039215652 Year: Pages: 240 DOI: 10.3390/books978-3-03921-565-2 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2019-12-09 16:10:12
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Building on advances in miniaturization and soft matter, surface tension effects are a major key to the development of soft/fluidic microrobotics. Benefiting from scaling laws, surface tension and capillary effects can enable sensing, actuation, adhesion, confinement, compliance, and other structural and functional properties necessary in micro- and nanosystems. Various applications are under development: microfluidic and lab-on-chip devices, soft gripping and manipulation of particles, colloidal and interfacial assemblies, fluidic/droplet mechatronics. The capillary action is ubiquitous in drops, bubbles and menisci, opening a broad spectrum of technological solutions and scientific investigations. Identified grand challenges to the establishment of fluidic microrobotics include mastering the dynamics of capillary effects, controlling the hysteresis arising from wetting and evaporation, improving the dispensing and handling of tiny droplets, and developing a mechatronic approach for the control and programming of surface tension effects. In this Special Issue of Micromachines, we invite contributions covering all aspects of microscale engineering relying on surface tension. Particularly, we welcome contributions on fundamentals or applications related to:Drop-botics: fluidic or surface tension-based micro/nanorobotics: capillary manipulation, gripping, and actuation, sensing, folding, propulsion and bio-inspired solutions; Control of surface tension effects: surface tension gradients, active surfactants, thermocapillarity, electrowetting, elastocapillarity; Handling of droplets, bubbles and liquid bridges: dispensing, confinement, displacement, stretching, rupture, evaporation; Capillary forces: modelling, measurement, simulation; Interfacial engineering: smart liquids, surface treatments; Interfacial fluidic and capillary assembly of colloids and devices; Biological applications of surface tension, including lab-on-chip and organ-on-chip systems. We expect novel as well as review contributions on all aspects of surface tension-based micro/nanoengineering. In line with Micromachines' policy, we also invite research proposals that introduce ideas for new applications, devices, or technologies.

Keywords

mist capillary self-alignment --- laser die transfer --- hydrophilic/superhydrophobic patterned surfaces --- microasssembly --- droplet transport --- microfluidics --- vibrations --- contact line oscillation --- asymmetric surfaces --- anisotropic ratchet conveyor --- surface tension --- capillary --- bearing --- wetting --- computational fluid dynamics --- droplet manipulation --- lab-on-a-chip --- microfluidics --- non-invasive control --- photochemical reaction --- photoresponsible surfactant --- surface tension --- two-phase flow --- wettability --- electrowetting --- actuation --- capillary pressure --- lab-on-a-chip --- Nasturtium leaf --- smart superhydrophobic surface --- hot drop --- condensation --- microtexture melting --- self-lubricating slippery surface --- wettability gradient --- electrosurgical scalpels --- anti-sticking --- soft tissue --- continuous-flow reactor --- mixing --- solutal Marangoni effect --- relaxation oscillations --- super-hydrophobic --- durable --- adhesion --- corrosive resistance --- droplet --- vibrations --- transport --- microfluidics --- self-cleaning surface --- superhydrophobic --- superhydrophilic --- superomniphobic --- microfluidics --- electrodynamic screen --- gecko setae --- micropipette-technique --- air-water surface --- oil-water interface --- soluble surfactant --- insoluble lipids --- “black lipid films” --- “droplet-interface-bilayers” --- equilibrium --- dynamic --- adsorption --- gas-microbubbles --- oil-microdroplets --- lung-surfactants --- nanoprecipitation --- microfluidics --- capillary gripper --- pick and place --- micromanufacturing --- two-photon polymerization --- stereolithography --- polydimethylsiloxane (PDMS) replication --- rigid gas permeable contact lenses --- wettability --- hydrophilic --- hydrophobic --- 355 nm UV laser --- surface treatment --- microstructure --- contact angle --- droplets --- liquid bridge --- microfabrication --- micromanipulation --- pick-and-place --- soft robotics --- surface tension --- wetting

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