Academic literature on the topic 'Irregular fibres'

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Journal articles on the topic "Irregular fibres"

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Furuno, Takeshi. "Bark Structure of Deciduous Broad-Leaved Trees Grown in the San'in Region, Japan." IAWA Journal 11, no. 3 (1990): 239–54. http://dx.doi.org/10.1163/22941932-90001181.

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The bark anatomy of 55 deciduous broadleaved tree species from the San'in Region is described. Anatomical features of ray and axial parenchyma cells, phloem fibres, and sclereids are tabulated. Individual species have their own characteristic bark structure. The diversity in tissue arrangement in the secondary phloem could be classified according to the following types: 1a. Phloem fibres in concentric bands alternating with bands ofaxial parenchyma devoid of crystals and sieve elements; 1b. Fibre-sclereids (sclerotic fibres) in concentric bands; 2. As 1a, but fibre bands f1anked by chambered crystalliferous parenchyma; 3a. Broad rays sclerified and extending fanwise or with a very large clump of sclereids; 3b. In species with only narrow wood rays, part of the rays dilated to produce fanwise extensions; 4. Aggregate rays with fanwise extensions; 5. Phloem fibres in round or spindle-shaped clusters or irregular, short bands; 6. Phloem sclereids in round or spindle-shaped clusters or irregular, short bands; 7. Diffuse distribution of all phloem elements; 8. Convergence ofrays towards the cortex.
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Hamza, A. A., T. Z. N. Sokkar, M. A. El-Bakary, and A. M. Ali. "Variable wavelength microinterferometry applied for irregular fibres." Journal of Optics A: Pure and Applied Optics 4, no. 4 (May 23, 2002): 371–76. http://dx.doi.org/10.1088/1464-4258/4/4/301.

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Hamza, A. A., M. A. Amer, H. I. Abd El-Kader, and A. M. Nasr. "Interferometric studies on fibres with irregular transverse sections." Polymer Testing 12, no. 4 (1993): 299–310. http://dx.doi.org/10.1016/0142-9418(93)90037-p.

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Hippeli, Susanne, Kerstin Dornisch, Thorsten Wiethege, Adrian Gillissen, Klaus-Michael Müller, and Erich F. Elstner. "Biological Durability and Oxidative Potential of Man-Made Vitreous Fibres as Compared to Crocidolite Asbestos Fibres." Zeitschrift für Naturforschung C 56, no. 7-8 (August 1, 2001): 633–48. http://dx.doi.org/10.1515/znc-2001-7-825.

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In this study we investigated relationships between redox properties and biodurability of crocidolite asbestos fibres and three different man-made vitreous fibres (MMVF): traditional stone wool fibres (MMVF 21), glass fibres (MMVF 11) and refractory ceramic fibres (RCF). Each fibre type was incubated up to 22 weeks in four different incubation media: gamble solution (GS) pH 5.0 and pH 7.4, representing blood plasma without proteins, and surfactant­ like solution (SLS) pH 5.0 and pH 7.4. During incubation time aliquots of incubation mixtures were removed and analysed in a biochemical model reaction, mimicking activated phagocytes. In addition, changes of fibre morphology and chemical composition were examined using SEM-and EDX-technology.In the presence of crocidolite asbestos fibres and MMVF 21 the formation of OH-radicals according to the Haber-Weiss sequence could be demonstrated, whereas MMVF 11 and RCF showed no reactivity. Crocidolite asbestos fibres exhibited a significant higher activity com­pared with the stone wool fibres at the onset of incubation. The oxidative capacities of these fibre types were shown to depend on both specific surface area and iron content. The oxidative potentials of crocidolite asbestos fibres as well as MMVF 21 were not constant during incubation over several weeks in each incubation medium. The reactivities showed sinoidal curves including reactivities much higher than those at the onset of incubation time. These irregular changes of oxidative capacity may be explained by changes of the redox state of fibre surface-complexed iron.Furthermore our results showed clear differences between incubation of fibres in GS and SLS, respectively, indicating that phospholipids play an important part in fibre dissolution behaviour and oxidative reactivity.In conclusion we suggest, that biodurability testing procedures should not exclusively concentrate on dissolution rates of fibres. They should include fibre characteristics concerning known pathogenic mechanisms to evaluate the real toxic potential of the fibre type looking at. Secondly we suggest, that phospholipids should be constituents of incubation liquids used for standardised fibre biodurability test procedures thus representing more realistic incubation conditions
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Hamza, A. A., T. Z. N. Sokkar, and M. A. Kabeel. "Multiple-beam interferometric studies on fibres with irregular transverse sections." Journal of Physics D: Applied Physics 18, no. 9 (September 14, 1985): 1773–80. http://dx.doi.org/10.1088/0022-3727/18/9/008.

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El-Tonsy, M. M. "Stress birefringence in compressible polymer fibres with irregular transverse sections." Journal of Materials Science 26, no. 11 (1991): 2857–60. http://dx.doi.org/10.1007/bf01124813.

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Wang, Chong, and Min Wang. "Formation of Core–Shell Structures in Emulsion Electrospun Fibres: A Comparative Study." Australian Journal of Chemistry 67, no. 10 (2014): 1403. http://dx.doi.org/10.1071/ch14214.

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Electrospinning has attracted great attention in recent years from different industries including biomedical engineering. Owing to the relative ease of fabricating ultrafine fibres with core–shell structures, emulsion electrospinning has been investigated intensively for making nanofibrous delivery vehicles for local and sustained release of bioactive or therapeutic substances, especially biomolecules such as growth factors. In preparing emulsions for electrospinning, different surfactants, ionic or non-ionic, can be used, which may subsequently influence the evolution of the core–shell structure in the electrospun emulsion jet or fibre. In this investigation, emulsions consisting of deionized water or phosphate buffer saline as the water phase, a poly(lactic-co-glycolic acid) solution as the oil phase and Span 80 (a non-ionic surfactant) or sodium dodecyl sulfate (an ionic surfactant) were electrospun into fibres for studying the core–shell structure and its evolution in emulsion electrospun fibres. Different microscopies were employed to study the morphological changes of the water phase in fibre samples collected at different locations along the jet (or fibre) trajectory during emulsion electrospinning. It was found that the evolution of the fibre core–shell structure was significantly different when different surfactants were used. If Span 80 was the surfactant, the water phase within the thick emulsion jet (or fibre) close to the Taylor cone existed in a discrete state whereas in ultrafine fibres collected beyond a certain distance from the Taylor cone, a mostly continuous water-phase core was observed. If sodium dodecyl sulfate was the surfactant, the core–shell structure in the thick jet (or fibre) was irregular but relatively continuous. A single core core–shell structure was eventually developed in ultrafine fibres. The core–shell structure in electrospun fibres and its evolution were also affected by the emulsion composition (e.g. polymer solution concentration, water-phase volume, and ion addition in the water phase).
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Yu, J. "Elastic tissues of the intervertebral disc." Biochemical Society Transactions 30, no. 6 (November 1, 2002): 848–52. http://dx.doi.org/10.1042/bst0300848.

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Elastic fibres have been generally considered to play no significant role in the mechanical functioning of the intervertebral disc since earlier studies reported that the elastic fibre network was sparse and irregular. However, a recent study has reported that the network is highly organized and that the distribution and orientation of elastic fibres varies from region to region. In the annulus, elastic fibres appear densely distributed in the region between the lamellae and also in ‘bridges’ across the lamellae. They are also organized in the nucleus where long straight fibres are radially oriented and anchor perpendicularly or obliquely into the cartilaginous endplate. Immunohisto-chemistry using specific antibodies indicates that elastin is present in the network, as is fibrillin. Biochemical studies show, however, that the amino acid composition of the residue remaining after alkaline (NaOH) extraction or CNBr digestion contains a higher concentration of polar amino acids than ligamentum nuchal elastin. The composition of the residue suggests that disc elastin may cross-link strongly with some other matrix components. With such coupling, it is thought that elastic fibres could play a significant mechanical role even though overall elastin is less than 5% of the total dry weight of the disc.
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Moradi, Sepehr, Xin Liu, Saeed Shaikhzadeh Najar, and Xungai Wang. "Tensile strength prediction of irregular fibres using diameter-dependent Weibull analysis." Journal of The Textile Institute 110, no. 4 (September 26, 2018): 600–605. http://dx.doi.org/10.1080/00405000.2018.1500087.

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URIZ, MARÍA J., and EMMA CEBRIAN. "Presence of the Indo–Pacific genus Petrosaspongia Bergquist, 1995 (Porifera: Demospongiae) in the Atlantic with description of a new species (P. pharmamari n. sp.)." Zootaxa 1209, no. 1 (May 22, 2006): 61. http://dx.doi.org/10.11646/zootaxa.1209.1.3.

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One specimen of a keratose sponge not ascribable to any known Atlantic genus was collected by scuba diving from the shallow rocky sublittoral of El Hierro (Canary Islands). The sponge is irregularly massive and very hard in consistency, with a microconulose and unarmoured surface. The skeleton is formed by primary fibres cored with abundant foreign debris and a densely reticulate network of secondary fibres, which are strongly laminated and free of foreign debris. An irregular tertiary network formed by very thin fibres is also visible in some places. The features of the skeleton differ from those of any genus known from the Atlantic Ocean but match those of the genus Petrosaspongia Bergquist described from the Indo-Pacific and represented up to now by the species P. nigra. The Atlantic species, here described as Petrosaspongia pharmamari n. sp., differs from P. nigra by its external colour (dark brown instead of black), its consistency (a little more compressible), the greater width of the primary and secondary fibres, the higher proportion of primary fibres and the smaller diameter of meshes. The finding of a second species confirms the validity of the genus Petrosaspongia. This is the first confirmed record of the genus outside the type locality.
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Dissertations / Theses on the topic "Irregular fibres"

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He, Wendy Weiyu, and wendy he@deakin edu au. "The mechanical behaviour of irregular fibre materials." Deakin University. School of Engineering and Technology, 2002. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20061208.081806.

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This work investigates the effect of fibre irregularities on the mechanical behaviour of the irregular fibres using the finite element method (FEM). The first part of this work examines that the effect of fibre dimensional irregularities on the linear and non-linear tensile behaviour of the fibres, using a two-dimensional (2D) finite element models. In the linear simulation, a concept of method Young’s modulus is introduced. The method Young’s modulus, breaking load and breaking extension are affected by the magnitude and frequency of diameter variation in the fibre specimen. Fibre dimensional variation and the gauge length effect are also simulated. In the non-linear analysis, some additional information is obtained on changes in the yield and post-yield regions, which are clearly shown in the load-extension curves. Further investigation is focused on the flexural buckling behaviour of fibres with dimensional irregularities. A three-dimensional (3D) finite element model is used to simulate the buckling deformation of dimensionally irregular fibres, and the critical buckling load of the simulated fibre is calculated. Two parameters, the effective length and the average diameter within the effective length of an irregular fibre, are considered to be the key factors that influence the buckling behaviour of the fibre. An important aspect of this work is the calculation of the effective length of an irregular fibre specimen during buckling. This method has not been reported before. The third part of this work is on the combined tensile and torsional behaviour of fibres with dimensional irregularities, using a three-dimensional (3D) finite element model. Two types of fibres, polyester and wool, are simulated with sine waves of different level (magnitude) and frequency at different twist levels. For the polyester fibre, experiment verification of the simulation results has been carried out, and the results indicate the FE model is well acceptable for the simulation. The final part of this work examines the combined effect of dimensional and structural irregularities on the fibre tensile behaviour. Three-dimensional (3D) finite element models are used to simulate the cracks (transverse, longitudinal, combined transverse and longitudinal cracks) and cavities distributed in uniform fibres and fibres with 30% level of diameter variation, respectively. One of important conclusions is that under the simulated conditions, the dimensional irregularity of fibre influences the tensile behaviour of fibres more than the fibre structural irregularity. The fibre dimensional irregularity affects not only the values of the breaking load and breaking extension, but also the shape of load-extension curves. However, the fibre structural irregularity simulated in the study appears to have little effect on the shape of the load-extension curves. In addition, the effect of crack or cavity size, type and distribution on fibre tensile properties is also investigated.
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Sjölander, Andreas. "Analyses of shotcrete stress states due to varying lining thickness and irregular rock surfaces." Licentiate thesis, KTH, Betongbyggnad, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-205311.

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Shotcrete is sprayed concrete applied pneumatically under high pressure and was invented in the beginning of the 1900's. This new technique decreased the construction time and since steel fibres were introduced in the shotcrete during the 1970's, shotcrete has been the primary support method for tunnels. Tunnels excavated with the drill and blast method creates a highly irregular rock surface which results in a shotcrete lining with varying thickness. The structural behaviour as well as the loads acting on the shotcrete lining depends on the interaction between the shotcrete, rock and rock bolts. There are several parameters influencing this interaction, e.g. bond strength, the stiffness of the rock and thickness of the shotcrete. All of these parameters are difficult to predict accurately which makes the structural design of the lining to a complex problem. This thesis present the first part of a research project with the long-term goal to improve the understanding of the structural behaviour of the shotcrete lining. To achieve this, numerical modelling have been used to study the build up of stresses and cracking of shotcrete when subjected to restrained loading caused by e.g. temperature differences and drying shrinkage. The response in the lining when subjected to a gravity load from a block has also been studied. The model is capable of describing the non-linear deformation behaviour of both plain and fibre reinforced shotcrete and uses presented in situ variations in thickness to more accurately account for the effects of expected variations in thickness. The thesis discuss and demonstrate the effect of important loads that acts on the shotcrete lining and how the irregular geometry of the rock surface in combination with the varying thickness of the shotcrete affect the development of stresses in the lining. It is also discussed how a full or partial bond failure affect the structural capacity of a shotcrete lining.
Sprutbetong är betong som appliceras pneumatiskt under högt tryckt, en metod utvecklad i början av 1900-talet. Kort därefter gjordes de första försöken att använda sprutbetong som bergförstärkning. Den här nya tekniken minskade produktionstiden och när stålfibrer introduceras under 1970-talet kunde det tunga arbetet med att placera armering minimeras. Sedan dess har sprutbetong blivit den preliminära förstärkningsmetoden, särskilt för tunnlar i hårt berg där tunna lager av sprutbetong ibland kan användas som den enda förstärkningsåtgärden.  Tunnlar byggs normalt genom metoden "borrning-sprängning" vilket leder till att bergytan där sprutbetongen appliceras få r en oregelbunden form. Under sprutning är det svårt att fastställa den exakta tjockleken och sprutbetongen har därmed en oregelbunden tjocklek. Beroende på in situ förhållanden kan oarmerad eller fiberarmerad sprutbetong i kombination med bergbultar användas för att förstärka berget. Det strukturella beteendet och lasterna som påverkar förstärkningen beror på interaktionen mellan sprutbetong, berg och bergbultar. Denna samverkan styrs av flera parametrar som t ex; vidhäftningshållfastheten, bergets styvhet och tjockleken hos sprutbetongen. Dessa parametrar är svåra att förutsäga vilket gör dimensionering av en sprutbetongförstärkningen till ett komplext problem. Den här uppsatsen presenterar den första delen av ett forskningsprojekt med det långsiktiga målet att öka förståelsen för det strukturella beteendet hos en sprutbetongförstärkning. För att uppnå detta har numerisk modellering använts för att studera spänningsuppbyggnaden och uppsprickningen av sprutbetong som utsätts för förhindrade rörelser orsakade av temperaturförändringar eller uttorkningskrympning. Sprutbetongens beteende när den utsätts för en blocklast har också studerats. En numeriskt modell för att analysera spänningarna i sprutbetong som tar hänsyn till tidsberoende materialegenskaper har använts. Modellen kan beskriva det icke-linjära deformationsbeteendet av oarmerad samt fiberarmerad sprutbetong och använder sig av presenterad fältdata för att beskriva de förväntade tjockleksvariationerna. Uppsatsen disskuterar och demonstrerar effekten av viktiga laster som verkar på sprutbetongförstärkningen och hur bergets oregelbundna yta i kombination med sprutbetongens varierande tjocklek påverkar spänningsuppbyggnaden i förstärkningen. Det diskuteras också hur ett fullständigt eller partiellt vidhäftningsbrott på verkar sprutbetongförstärkningens bärförmåga.

QC 20170418

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Paluba, Robert. "Geometry of complex character varieties." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS155/document.

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Le but de cette thèse est d'étudier différents exemples des variétés de caractères régulières et sauvages des courbes complexes.La première partie est consacrée à l'étude d'un exemple de variété de caractères de la sphère avec quatre trous et groupe exotique G₂ comme son groupe de structure. On démontre que pour un choix particulier de classes de conjugaison du groupe G₂ , la variété obtenue est de dimension complexe deux et isomorphe à la surface cubique de Fricke—Klein. Cette surface apparaît déjà dans le cas classique comme la variété de caractères de cette surface avec le groupe de structure SL₂ (C). De plus, on interprète les orbites de groupe de tresses de taille 7 dans cette surface comme les droites passant par les triplés de points dans le plan de Fano P² (F₂).Dans la deuxième partie, on établit plusieurs cas de la „conjecture d'écho”, correspondant aux équations différentielles de Painlevé I, II et IV. On montre que sur la sphère de Riemann avec un point singulier, pour des choix particuliers de la singularité il y a trois familles infinies de variétés de caractères sauvages de dimension complexe deux. Dans ces familles, le rang du groupe de structure n'est pas borné et augmente jusqu'à l'infini. Le résultat principal de cette partie démontre que tous les membres de ces trois familles de variétés sont isomorphes aux espaces de phase des équations de Painlevé associées. En calculant les quotients de la théorie géométrique des invariants, on fournit des isomorphismes explicites entre les anneaux de fonctions des variétés affines qui apparaissent et relie les paramètres des surfaces cubiques.Dans la dernière partie, avec des outils de la géométrie quasi-Hamiltonienne, on étudie une famille des espaces généralisant les hiérarchies de Painlevé I et II pour les groupes linéaires de rang supérieur. En particulier, pour toute variété Bk dans la hiérarchie il y a une application moment, prenant ses valeurs dans un groupe, qui s'avère être un polynôme continuant d'Euler. Ces polynômes admettent des factorisations en continuants plus courts et on montre que les factorisations d'un polynôme continuant de longueur k en termes de longueur un sont énumérées par le nombre de Catalan Ck. De plus, chaque factorisation fournit un plongement du produit de fusion de k copies de GLn (C) sur un ouvert dense de Bk et on démontre que ces plongements relient les structures quasi-Hamiltoniennes. Finalement, on utilise ce résultat pour dériver une formule explicite pour la 2-forme quasi-Hamiltonienne sur Bk, généralisant la formule connue dans le cas de B₂
The aim of this thesis is to study various examples of tame and wild character varieties of complex curves.In the first part, we study an example of a tame character variety of the four-holed sphere with simple poles and exotic group G₂ as the structure group. We show that for a particular choice of conjugacy classes in G₂, the resulting affine symplectic variety of complex dimension two is isomorphic to the Fricke-Klein cubic surface, known from the classical case of the character variety for the group SL₂(C). Furthermore, we interpret the braid group orbits of size 7 in this affine surface as lines passing through triples of points in the Fano plane P²(F₂).In the second part, we establish multiple cases of the so-called „echo conjecture”, corresponding to the cases of Painleve I, II and IV differential equations. We show that for the Riemann sphere with one singular point and suitably chosen behavior at the singularity, there are three infinite families of wild character varieties of complex dimension two. In these families, the rank of the structure group is not bounded and goes to infinity. The main result of this part shows that in each family all the members are affine cubic surfaces, isomorphic to the phase spaces of the aforementioned Painleve equations. By computing the geometric invariat theory quotients, we provide explicit isomorphisms between the rings of functions of the arising affine varieties and relate the coefficients of the affine surfaces.The last part is dedicated to the study of a family of spaces generalizing the Painleve I and II hierarchies for higher rank linear groups, which is done by the means of quasi-Hamiltonian geometry. In particular, for each variety Bk in the hierarchy there is a group-valued moment map and they turn out to be the Euler's continuant polynomials. These in turn admit factorisations into products of shorter continuants and we show that for a continuant of length k, the distinct factorisations into continuants of length one are counted by the Catalan number Ck. Moreover, each such factorisation provides an embedding of the fusion product of k copies of GLn(C) onto a dense open subset of B_k and the quasi-Hamiltonian structures do match up. Finally, using this result we derive the formula for the quasi-Hamiltonian two form on the space Bk, which generalises the formula known for the case of B₂
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Bogren, Oliver, and Simon Olofsson. "Piezoelektrisk energiskördning för oregelbundna lågfrekventa rörelser." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-191140.

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Energiskördning är idag ett växande område och är framstående sett till hållbarhetsaspekterna. Vibrationsbaserad sådan har blivit allt populärare där man kan utnyttja mekanisk energi från olika källor till att generera elektrisk energi. Piezoelektricitet fungerar enligt denna princip och piezoelektrisk energiskördning har varit ett område som fler och fler utnyttjar på grund av dess effektivitet, exempelvis till trådlösa sensornätverk. Ett krav på att piezoelektrisk energiskördning ska fungera optimalt är att vibrationerna sker med en satt frekvens utan större variation, ofta i väldigt höga frekvenser. Syftet med detta projekt är att anpassa denna teknik till mänskliga rörelser vilket kan göra den mer användbar och ett tänkt ändamål kan vara ett demonstrationsexempel för oregelbundna rörelser vid låga frekvenser, precis som mänskliga rörelser. Utmaningen lägger därmed i att utveckla en piezoelektrisk energiskördare som har ett frekvensområde inom mänskliga rörelsers frekvenser på 4 till 7 Hertz, där effektiviteten fortfarande kan vara hög. Detta har beprövats med vibrationsplatta. Vad som observerades var att med flera piezoelektriska material på konsolbalkar i kolfiber av olika dimensioner med olika vikter längst ut, uppstod ett frekvensområde inom mänskliga området med höga spänningar. För att göra det möjligt behövdes vikterna ha en stor massa av upp till hundratals gram så att resonansfrekvenserna kunde vara inom nämnt frekvensområde. Då piezoelektriska material ger en växelspänning, måste spänningen likriktas. Detta gjordes med två olika gränssnitt med ett mönsterkort tillverkat för vardera. Dessa gränssnitt är ett klassiskt som helt enkelt likriktar spänningen, medan den andra, Parallel Synchronized Switch Harvesting on the Inductor (P-SSHI), ska maximera spänningen och effekten. Det visade sig att det inte blev lika lyckat som planerat. Det klassiska gränssnittet gav en likspänning som var nästan lika hög som den inmatade växelspänningen medan det inte gällde för P-SSHI.
Today energy harvesting is an area on the rise and is outstanding in regards to the environmental aspects. Vibration based energy harvesting has become popular where it uses mechanical energy from different sources to produce electrical energy. Piezoelectricity operates according to this principle and piezoelectric energy harvesting has been an area more are using because of its efficiency, with applications such as wireless sensor networks. One demand for piezoelectric energy harvesting to work optimally is that the vibration source must have a well known frequency with minor deviations and this in usually very high frequencies. The purpose of this thesis is to adapt this technology to human motions which could make it even more useful and a proposed usage is a demo product for irregular motions of low frequency, just like human motions. The challenge is hence to create a piezoelectric energy harvester which has a frequency range within the human motions’ frequencies of 4 to 7 Hertz, where the efficiency still could be high. This has been tested using a vibration exciter. What was noticed was that with multiple piezoelectric materials on cantilever beams of carbon fibre with different dimensions and tip masses, a frequency range within human range with high voltages could be created. To make this possible, the masses needed to have a significant mass of up towards hundreds of grams in order for the resonance frequencies to be within the stated frequency range. As the piezoelectric materials provide an AC voltage, the voltage needs to be rectified. This was done with two different interfaces with a PCB created for each. These interfaces are a classic one which simply rectifies the voltage, while the other, Parallel Synchronized Switch Harvesting on the Inductor (PSSHI), is supposed to maximize the voltage and power. This did not turn out to be as successful as predicted. The classical interface delivered a DC voltage almost as much as the provided AC voltage while the P-SSHI interface did not.
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Books on the topic "Irregular fibres"

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Microwave approach to highly-irregular fiber optics. New York: Wiley, 1998.

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Book chapters on the topic "Irregular fibres"

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Bentosela, F. "Propagation in Irregular Optic Fibres." In Mathematical Results in Quantum Mechanics, 293–98. Basel: Birkhäuser Basel, 1994. http://dx.doi.org/10.1007/978-3-0348-8545-4_35.

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Jaroszewicz, Leszek R., Zbigniew Krajewski, and Krzysztof P. Teisseyre. "The Possibility of a Continuous Monitoring of the Horizontal Buildings’ Rotation by the Fibre-Optic Rotational Seismograph AFORS Type." In Seismic Behaviour and Design of Irregular and Complex Civil Structures, 339–51. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-5377-8_23.

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Jaroszewicz, Leszek R., Anna Kurzych, Zbigniew Krajewski, Jerzy K. Kowalski, and Krzysztof P. Teisseyre. "FOSREM: Fibre-Optic System for Rotational Events and Phenomena Monitoring: Construction, Investigation and Area of Application." In Seismic Behaviour and Design of Irregular and Complex Civil Structures II, 49–64. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-14246-3_5.

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Liu, Shuting, Yingguang Li, Yingxiang Shen, and Yee Mey Goh. "A Multi-Zoned Self-Resistance Electric Heating Method for Curing Irregular Fiber Reinforced Composite Parts." In Advances in Transdisciplinary Engineering. IOS Press, 2021. http://dx.doi.org/10.3233/atde210028.

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Fibre Reinforced Polymers (FRP) have been widely applied in various industries due to their outstanding properties. As a promising curing technology for FRP parts, the self-resistance electric (SRE) heating method has attracted plenty of attention. However, it is difficult for the SRE heating method to uniformly cure the FRP parts with irregular structures. In this paper, a multi-zoned SRE heating method is proposed, in which the FRP part is divided into several heating zones and the temperature of each zone is regulated independently. A multi-channel electrical voltage control system is developed to realise the multi-zoned SRE heating of a wing-shaped FRP part, in which a rapid zone-based temperature control responsiveness is achieved, and the maximum temperature difference is reduced from 60 °C to less than 10 °C, reaching 2.5 °C at its best. This work presents an alternative for the high efficiency and energy-saving curing process of FRP parts.
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Santoso, Y. E., Tai-Shung Chung, Kai Yu Wang, and Martin Weber. "The investigation of irregular inner skin morphology of hollow fiber membranes at high-speed spinning and the solutions to overcome it." In Hollow Fiber Membranes, 105–22. Elsevier, 2021. http://dx.doi.org/10.1016/b978-0-12-821876-1.00023-8.

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Chróścielewski, J., S. Burzyński, A. Sabik, B. Sobczyk, and W. Witkowski. "Nonlinear FEM analysis of irregular shells composed of fiber metal laminates." In Shell Structures: Theory and Applications Volume 4, 363–66. CRC Press, 2017. http://dx.doi.org/10.1201/9781315166605-82.

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Saltzman, W. Mark. "Cell Adhesion." In Tissue Engineering. Oxford University Press, 2004. http://dx.doi.org/10.1093/oso/9780195141306.003.0011.

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The external surface of the cell consists of a phospholipid bilayer which carries a carbohydrate-rich coat called the glycocalyx; ionizable groups within the glycocalyx, such as sialic acid (N-acetyl neuraminate), contribute a net negative charge to the cell surface. Many of the carbohydrates that form the glycocalyx are bound to membrane-associated proteins. Each of these components— phospholipid bilayer, carbohydrate-rich coat, membrane-associated protein—has distinct physicochemical characteristics and is abundant. Plasma membranes contain ∼50% protein, ∼45% lipid, and ∼5% carbohydrate by weight. Therefore, each component influences cell interactions with the external environment in important ways. Cells can become attached to surfaces. The surface of interest may be geometrically complex (for example, the surface of another cell, a virus, a fiber, or an irregular object), but this chapter will focus on adhesion between a cell and a planar surface. The consequences of cell–cell adhesion are considered further in Chapter 8 (Cell Aggregation and Tissue Equivalents) and Chapter 9 (Tissue Barriers to Molecular and Cellular Transport). The consequences of cell–substrate adhesion are considered further in Chapter 7 (Cell Migration) and Chapter 12 (Cell Interactions with Polymers). Since the growth and function of many tissue-derived cells required attachment and spreading on a solid substrate, the events surrounding cell adhesion are fundamentally important. In addition, the strength of cell adhesion is an important determinant of the rate of cell migration, the kinetics of cell–cell aggregation, and the magnitude of tissue barriers to cell and molecule transport. Cell adhesion is therefore a major consideration in the development of methods and materials for cell delivery, tissue engineering, and tissue regeneration. The most stable and versatile mechanism for cell adhesion involves the specific association of cell surface glycoproteins, called receptors, and complementary molecules in the extracellular space, called ligands. Ligands may exist freely in the extracellular space, they may be associated with the extracellular matrix, or they may be attached to the surface of another cell. Cell–cell adhesion can occur by homophilic binding of identical receptors on different cells, by heterophilic binding of a receptor to a ligand expressed on the surface of a different cell, or by association of two receptors with an intermediate linker. Cell–matrix adhesion usually occurs by heterophilic binding of a receptor to a ligand attached to an insoluble element of the extracellular matrix.
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Conference papers on the topic "Irregular fibres"

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Cirka, H., W. Farr, S. Koehler, and K. Billiar. "Extending Standard Rotational Rheometry for Small, Irregular, Anisotropic Tissues and Gels." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53678.

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Quantification of the viscoelastic properties of soft tissues and protein gels is vital to the understanding of normal tissue development and disease progression and for evaluating the cell-mediated remodeling of fibrous protein-based engineered tissues (e.g., collagen, fibrin). Rotational (shear) rheometers are theoretically well suited for characterizing the storage and loss modulus of such soft gels; however, standard “geometries” used in such devices require relatively large, homogeneous samples to generate sufficient torque for accurate analysis of very soft materials, and the analysis generally assumes linear isotropic viscoelastic behavior. Newly formed tissues and biological protein gels such as blood clots are often small, soft (low stiffness), irregularly shaped, anisotropic, and difficult to handle. The aim of this work is to develop a method that will allow the accurate characterization of small, irregular protein gels utilizing an industry-standard rheometer.
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Challa, Sushmita, M. Shafquatul Islam, Danming Wei, Jasmin Beharic, Dan O. Popa, and C. K. Harnett. "Functional Fiber Junctions for Circuit Routing in E-Textiles: Deterministic Alignment of MEMS Layout With Fabric Structure." In ASME 2021 16th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/msec2021-63887.

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Abstract Fabrics and fibrous materials offer a soft, porous, and flexible substrate for microelectromechanical systems (MEMS) packaging in breathable, wearable formats that allow airflow. Device-on-fiber systems require developments in the field of E-Textiles including smart fibers, functional fiber intersections, textile circuit routing, and alignment methods that adapt to irregular materials. In this paper, we demonstrate a MEMS-on-fabric layout workflow that obtains fiber intersection locations from high-resolution fabric images. We implement an image processing algorithm to drive the MEMS layout software, creating an individualized MEMS “gripper” layout designed to grasp fibers on a specific fabric substrate during a wafer-to-fabric parallel transfer step. The efficiency of the algorithm in terms of a number of intersections identified on the complete image is analyzed. The specifications of the MEMS layout design such as the length of the MEMS gripper, spatial distribution, and orientation are derivable from the MATLAB routine implemented on the image. Furthermore, the alignment procedure, tolerance, and hardware setup for the alignment method of the framed sample fabric to the wafer processed using the custom gripper layout are discussed along with the challenges of the release of MEMS devices from the Si substrate to the fabric substrate.
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Challa, Sushmita, and Cindy Harnett. "Packaging Electronics on Textiles: Identifying Fiber Junctions for Automated Placement." In ASME 2020 15th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/msec2020-8456.

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Abstract Electronic textile (E-textile) research requires an understanding of the mechanical properties of fabric substrates used to build and support electronics. Because fibers are often non-uniform and fabrics are easily deformed, locating fiber junctions on the irregular surface is challenging, yet is essential for packaging electronics on textiles at the resolution of single fibers that deliver power and signals. In this paper, we demonstrate the need to identify fiber junctions in a task where microelectromechanical structures (MEMS) are integrated on fabrics. We discuss the benefits of fiber-aligned placement compared with random placement. Thereafter we compare three image processing algorithms to extract fiber junction locations from sample fabric images. The Hough line transform algorithm implemented in MATLAB derives line segments from the image to model the fibers, identifying crossings by the intersections of the line segments. The binary image analysis algorithm implemented in MATLAB searches the image for unique patterns of 1s and 0s that represent the fiber intersection. The pattern matching algorithm implemented in Vision Assistant - LabVIEW, uses a pyramid value correlation function to match a reference template to the remainder of the fabric image to identify the crossings. Of the three algorithms, the binary image analysis method had the highest accuracy, while the pattern matching algorithm was fastest.
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Binetruy, Christophe, Sébastien Comas-Cardona, and Fan Zhang. "Identification and Modeling of Variability in Fabrics Used as Reinforcement in Polymer Composites: Influence on Transport and Mechanical Properties." In ASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/esda2012-82581.

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Variability in fiber architecture and content introduces randomness in transport and mechanical properties of textile reinforcements and composites. Assessment of robustness of both manufacturing processes and composite parts require to link fabric variability to dominant properties. Irregular injection flow patterns or defects in the final products often occur due to the high variability in the fibrous media. Therefore, manufacturing robustness and part reliability have to be studied to avoid trial and error procedures. This study focuses on spatial variability in the fiber volume fraction and architecture and their influence on permeability of fiber reinforcements and mechanical performance of textile composite, relating these important properties to variation in reinforcement architecture. Methods to capture experimentally and model numerically the fabric randomness are presented and illustrated on typical non-woven fabrics. An efficient numerical approach is presented for the simulation of mold filling process with random fibrous permeability as input. Numerical examples for different injection schemes are presented to demonstrate the ability of the current approach in predicting the variability in mold filling results.
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Chen, Y. C., and H. G. Winful. "Irregular And Chaotic Behavior Of Semiconductor Lasers Under Modulation." In Cambridge Symposium-Fiber/LASE '86, edited by O. G. Ramer and Paul Sierak. SPIE, 1987. http://dx.doi.org/10.1117/12.937462.

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Koike-Akino, Toshiaki, Congzhe Cao, Ye Wang, Keisuke Kojima, David S. Millar, and Kieran Parsons. "Irregular Polar Turbo Product Coding for High-Throughput Optical Interface." In Optical Fiber Communication Conference. Washington, D.C.: OSA, 2018. http://dx.doi.org/10.1364/ofc.2018.tu3c.5.

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Sultana, Quazi Nahida, Saheem Absar, Stephanie Hulsey, Hans Schanz, and Mujibur Khan. "Synthesis and Processing of Solution Spun Cellulose Acetate Fibers Reinforced With Carbon Nanotubes." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50804.

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We report the fabrication of Cellulose Acetate (CA) based fibers reinforced with Multi-Walled Carbon Nanotubes (MWCNTs) using a solution spinning process. The motivation of this work is to produce high performance fibers based on sustainable natural materials as an alternative to synthetic fibers for structural applications. A 30 wt% solution of CA in a binary solvent system of N, N-dimethylacetamide (DMAc) and Acetone (3:7 v/v) was used for the solution spinning of CA fibers. Both neat and CNT-loaded CA fibers were produced. The CNT loading with respect to the polymer was at 0.5 wt%. For CA-MWCNT spinning solutions, the MWCNTs were initially dispersed in the solvent and then CA is added and mixed together. The mixing temperature kept 40–45°C. The viscosity of the CA solution was 8,000 cP. Addition of MWCNT increased the viscosity of the CA solution to 32,000 cP. A lab-scale solution spinning line consisting of a constant torque high temperature gear pump and heated extrusion channels was used to produce both neat and CA-MWCNT fibers. The solution was pumped through a spinneret at the end of the extrusion channel with an orifice as a viscous gel-like filament which was passed through a spool placed in a coagulation bath and then it formed as fiber. The fibers are collected to a takeup roll at a draw ratio of 8.0. Characterization studies of both neat and MWCNT loaded fibers were performed differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA) and scanning electron microscopy (SEM). DSC analysis of fibers showed reduction in crystallinity of CA upon inclusion of 0.5 wt% MWCNT. TGA analysis showed improvement of thermal stability in CA-MWCNT fibers compared to neat CA. Cross-sections of neat CA fibers showed smooth surfaces with no significant defects, while CA-MWCNT showed formation of micro-voids and irregular features. Longitudinal views of outer surface of both neat CA and CA-MWCNT fibers showed no indication of surface defects or protrusions.
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Minkovich, Vladimir P., Joel Villatoro, Alexander B. Sotsky, Maria Asuncion Illarramendi, Joseba Zubia, and Marcelo Vaca Pereira Ghirghi. "Special microstructured fibers with irregular and regular claddings for supercontinuum generation." In Third International Conference on Applications of Optics and Photonics, edited by Manuel Filipe P. Martins Costa. SPIE, 2017. http://dx.doi.org/10.1117/12.2271838.

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Schorr, T., W. Sauer-Greff, R. Urbansky, and H. F. Haunstein. "Design and Performance of High-Rate Irregular LDPC Codes for Turbo Equalization of PMD Channels." In OFC/NFOEC 2007 - 2007 Conference on Optical Fiber Communication and the National Fiber Optic Engineers Conference. IEEE, 2007. http://dx.doi.org/10.1109/ofc.2007.4348434.

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Tsunekawa, Y., M. Hiromura, and M. Okumiya. "Nitriding of Metal Droplets in Synthesis of Intermetallic Matrix Composite Coatings by Reactive RF Plasma Spraying." In ITSC 1998, edited by Christian Coddet. ASM International, 1998. http://dx.doi.org/10.31399/asm.cp.itsc1998p1143.

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Abstract This paper presents a novel process that uses RF plasma spraying and premixed elemental powders to produce intermetallic matrix composites in situ without having to add reinforcement fibers or particles. Splats were collected on a stainless steel substrate and were analyzed to determine if nitrides had formed in metal droplets during flight and how it affected splat morphology. The typical splat morphology of impinged Ti droplets is disk-type with an outer peripheral fringe. Aluminum splats, on the other hand, are classified into two categories: a disk-type with an irregular outer periphery and a semi-massive-type. Other composites produced and examined include TiAl, AlN, and Ti2AlN.
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